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ti
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s
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).
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h
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p
a
p
e
r
su
m
m
a
rize
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re
su
lt
s
fro
m
a
fiv
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r
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h
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c
o
n
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u
c
ted
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se
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h
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g
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g
li
s
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t
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terv
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n
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se
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s
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m
a
ti
c
a
n
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ly
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sin
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AX
QD
A
wa
s
c
h
o
se
n
fo
r
d
a
ta
a
n
a
ly
sis.
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d
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g
s
u
n
c
o
v
e
re
d
th
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m
e
s
th
a
t
e
m
e
rg
e
d
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m
t
h
e
d
a
ta,
wh
ich
m
ig
h
t
lay
t
h
e
fo
u
n
d
a
ti
o
n
f
o
r
c
las
sify
in
g
tea
c
h
e
rs
in
to
t
h
re
e
g
ro
u
p
s:
a
d
a
p
ti
v
e
o
rig
i
n
a
to
rs
(AO
s),
n
e
u
tral
p
ra
g
m
a
ti
sts
(NPs
),
a
n
d
trad
it
io
n
a
l
c
o
n
se
r
v
e
rs
(T
Cs).
M
o
st
TCs’
tea
c
h
in
g
p
h
i
lo
so
p
h
ies
we
re
tea
c
h
e
r
-
c
e
n
tere
d
a
n
d
su
p
p
o
rti
v
e
of
c
o
n
v
e
n
ti
o
n
a
l
tea
c
h
i
n
g
tec
h
n
iq
u
e
s.
S
ti
ll
,
t
h
e
NPs
a
c
k
n
o
wle
d
g
e
d
th
a
t
in
stru
c
ti
o
n
a
l
stra
teg
ies
n
e
e
d
e
d
to
be
c
h
a
n
g
e
d
.
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h
e
AOs
s
o
u
g
h
t
to
c
h
a
n
g
e
how
tea
c
h
e
rs
u
se
d
CT
;
t
h
e
y
a
c
ti
v
e
ly
p
u
t
stra
teg
y
i
n
t
o
p
lac
e
to
b
r
in
g
a
b
o
u
t
m
e
a
n
in
g
fu
l
c
h
a
n
g
e
.
T
h
e
se
re
su
lt
s
we
re
v
a
lu
a
b
le
re
fe
re
n
c
e
s
fo
r
h
ig
h
sc
h
o
o
l
tea
c
h
e
rs
to
a
ss
ist
th
e
ir
st
u
d
e
n
ts
with
b
e
tt
e
r
c
o
n
str
u
c
ti
v
ist
i
n
stru
c
ti
o
n
,
t
h
u
s
e
n
h
a
n
c
in
g
t
h
e
q
u
a
li
ty
of
tea
c
h
i
n
g
a
n
d
lea
rn
i
n
g
En
g
li
sh
in
th
e
4
.
0
e
ra
.
K
ey
w
o
r
d
s
:
C
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s
tr
u
ctiv
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h
in
g
E
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tio
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R
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rticle
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n
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CC
BY
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.
C
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p
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:
Ph
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T
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Kieu
Oan
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Facu
lty
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Fo
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d
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ca
tio
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h
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Ng
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Un
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er
s
ity
of
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Ng
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n
,
Vietn
am
E
m
ail:
o
r
io
lep
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am
.
f
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tn
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e@
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m
ail.
co
m
1.
I
NT
RO
D
UCT
I
O
N
Ov
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th
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p
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way
s
to
g
iv
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class
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m
teac
h
er
s
in
n
o
v
ativ
e
teac
h
in
g
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d
e
as,
lead
in
g
to
ed
u
ca
tio
n
al
i
m
p
r
o
v
e
m
en
ts
.
T
h
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ef
f
o
r
ts
in
clu
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e
b
etter
p
r
ep
ar
ati
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ten
t
a
r
ea
k
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e,
teac
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in
g
s
tr
ateg
ies,
an
d
class
r
o
o
m
m
an
a
g
em
en
t
[
1
]
.
As
a
r
esu
lt,
u
p
g
r
a
d
in
g
an
d
p
r
ep
a
r
in
g
f
o
r
th
e
teac
h
in
g
p
r
o
f
ess
io
n
en
co
m
p
ass
es
a
v
ar
iety
of
ac
tio
n
s
th
at
a
r
e
p
ar
t
of
th
e
r
ef
o
r
m
of
teac
h
er
ed
u
ca
tio
n
in
t
h
e
Vietn
am
ese
s
ettin
g
[
2
]
.
Acc
o
r
d
in
g
to
t
h
e
E
d
u
ca
tio
n
L
aw,
“tea
ch
er
s
h
o
ld
a
v
ital
p
o
s
itio
n
in
s
o
ciety
,
a
r
e
h
o
n
o
r
ed
by
s
o
ciety
,
an
d
p
lay
a
lead
in
g
p
ar
t
in
e
n
s
u
r
in
g
th
e
q
u
ality
of
ed
u
ca
tio
n
”
[
3
]
.
C
r
ea
tin
g
ef
f
ec
tiv
e
teac
h
er
s
is
one
of
th
e
m
o
s
t
f
u
n
d
am
en
ta
l
d
u
ties
of
teac
h
e
r
ed
u
ca
tio
n
p
r
o
g
r
a
m
s
.
E
d
u
ca
ti
o
n
al
r
esear
ch
h
as
d
em
o
n
s
tr
at
ed
th
at
co
n
s
tr
u
ctiv
is
m
can
h
elp
teac
h
er
s
cr
ea
te
more
s
tu
d
en
t
-
ce
n
ter
ed
class
r
o
o
m
en
v
ir
o
n
m
en
ts
an
d
in
cr
ea
s
e
th
e
v
is
ib
ilit
y
of
th
eir
s
tu
d
en
t
s
’
lear
n
in
g
[
4
]
,
[
5
]
.
“A
co
n
s
tr
u
ctiv
is
t
ap
p
r
o
ac
h
ai
m
s
to
h
el
p
p
u
p
ils
in
ter
p
r
et,
cr
ea
te,
an
d
r
e
o
r
g
a
n
ize
k
n
o
wl
ed
g
e
in
ac
tiv
e
an
d
in
d
iv
id
u
al
way
s
”
[
6
]
.
Fu
r
th
er
m
o
r
e,
th
e
th
e
o
r
y
s
tates
th
at
lear
n
in
g
is
a
“b
u
ild
in
g
p
r
o
ce
s
s
by
ac
tiv
e
s
tu
d
en
ts
in
ter
ac
tin
g
with
th
e
s
o
cial
an
d
p
h
y
s
ical
wo
r
ld
”
t
h
at
is
in
ter
p
r
etiv
e
an
d
r
ec
u
r
s
iv
e
[
7
]
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t
J
E
v
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&
R
es E
d
u
c
I
SS
N:
2252
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8
8
2
2
A
q
u
a
lita
tive
ca
s
e
s
tu
d
y
o
f c
o
n
s
tr
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ctivi
s
t te
a
ch
in
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a
t a
h
ig
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ch
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o
l in
a
n
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th
ern
…
(
P
h
a
m
Th
i Ki
eu
Oa
n
h
)
1437
In
Vietn
am
,
teac
h
er
ed
u
ca
tio
n
r
ef
o
r
m
s
h
av
e
g
e
n
er
ally
p
r
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ted
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s
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if
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f
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m
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ter
e
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e.
C
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s
tr
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cti
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t
teac
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in
g
(
C
T
)
,
wh
ich
en
co
u
r
ag
es
s
tu
d
e
n
ts
to
cr
ea
te
in
f
o
r
m
atio
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d
e
p
e
n
d
en
tly
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is
a
r
ec
en
t
e
d
u
ca
tio
n
al
r
ev
o
l
u
tio
n
th
at
r
eq
u
ir
es
teac
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er
s
to
s
tr
ay
f
r
o
m
tr
ad
itio
n
al
k
n
o
wled
g
e
tr
a
n
s
f
er
.
It
is
ev
id
en
t
th
at
in
th
e
co
n
s
tr
u
ctiv
is
t
class
,
th
e
f
o
cu
s
s
h
if
ts
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r
o
m
th
e
teac
h
er
’
s
v
o
ice
to
th
e
p
u
p
ils
’
v
o
ices.
A
class
r
o
o
m
is
no
lo
n
g
er
wh
e
r
e
th
e
teac
h
er
ac
ts
as
a
k
n
o
wled
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e
tr
a
n
s
m
itter
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d
p
o
u
r
s
in
f
o
r
m
atio
n
in
to
p
ass
iv
e
p
u
p
ils
.
In
s
u
ch
class
es,
p
u
p
ils
ar
e
m
o
tiv
ated
to
jo
in
th
e
lear
n
in
g
ac
tiv
ities
to
b
u
ild
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eir
k
n
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g
e
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el
y
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th
u
s
en
th
u
s
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ically
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th
em
in
v
o
lv
ed
in
th
e
less
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n
s
.
L
ea
r
n
e
r
s
’
k
n
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w
led
g
e
co
n
s
tr
u
ctio
n
is
b
eliev
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d
to
be
co
n
s
tr
u
cte
d
by
c
o
n
n
ec
tin
g
with
p
r
i
o
r
k
n
o
wled
g
e
t
h
r
o
u
g
h
CT
tech
n
iq
u
es.
T
h
e
teac
h
e
r
’
s
p
r
im
ar
y
d
u
ty
in
a
co
n
s
tr
u
cti
v
is
t
class
r
o
o
m
is
to
h
elp
s
tu
d
en
ts
g
en
er
ate
m
ea
n
in
g
th
r
o
u
g
h
m
ea
n
in
g
f
u
l
an
d
ac
tiv
e
e
x
p
er
ien
ce
s
;
u
n
lik
e
tr
ad
itio
n
al
class
r
o
o
m
s
,
wh
er
e
teac
h
er
s
’
in
s
tr
u
ctio
n
s
d
ep
en
d
on
tex
tb
o
o
k
s
,
p
u
p
ils
ar
e
m
o
tiv
ated
to
s
h
ar
e
th
eir
b
elief
s
an
d
v
iewp
o
in
ts
.
As
W
itfe
lt
[
8
]
s
tated
,
th
e
teac
h
er
’
s
r
o
le
in
CT
is
to
be
a
f
ac
ilit
ato
r
wh
o
p
r
o
v
id
es
g
u
id
an
ce
a
n
d
en
co
u
r
ag
es
th
e
p
u
p
ils
to
co
llab
o
r
ate,
d
is
co
v
e
r
s
th
e
p
u
p
ils
’
u
n
iq
u
e
ab
ilit
ies,
an
d
o
b
s
er
v
es
th
e
p
u
p
ils
’
d
u
ties
to
g
iv
e
h
elp
if
n
ee
d
ed
.
T
h
e
CT
ap
p
r
o
ac
h
ass
u
m
es
th
at
in
s
tead
of
th
e
two
s
id
es
in
th
e
lear
n
in
g
p
r
o
ce
s
s
,
a
teac
h
er
an
d
p
u
p
ils
n
ee
d
ef
f
ec
tiv
e
in
ter
ac
tio
n
an
d
co
llab
o
r
atio
n
to
war
d
s
ac
h
iev
in
g
a
co
m
m
o
n
g
o
al.
T
h
er
ef
o
r
e
,
th
is
s
tu
d
y
in
v
esti
g
ates
how
h
ig
h
s
ch
o
o
l
t
ea
ch
er
s
’
p
er
ce
p
tio
n
s
of
CT
h
av
e
ch
an
g
e
d
an
d
how
th
ey
ap
p
ly
CT
s
tr
ateg
ies
in
th
e
E
n
g
lis
h
class
r
o
o
m
.
T
h
e
m
ain
g
o
al
of
th
is
s
tu
d
y
is
to
in
v
esti
g
ate
wh
y
it
is
so
d
if
f
icu
lt
to
b
r
in
g
ab
o
u
t
CT
ch
an
g
e
in
Vietn
am
ese
h
ig
h
s
c
h
o
o
ls
.
T
h
e
f
o
l
l
o
w
i
n
g
q
u
e
r
i
e
s
we
r
e
a
n
s
w
e
r
e
d
to
a
c
h
i
e
v
e
t
h
es
e
g
o
a
l
s
:
i)
W
h
a
t
p
e
r
s
p
e
ct
i
v
es
do
E
n
g
l
i
s
h
t
e
a
c
h
e
r
s
in
h
i
g
h
s
c
h
o
o
l
s
h
a
v
e
r
e
g
a
r
d
i
n
g
c
o
n
s
t
r
u
c
t
i
v
i
s
t
i
n
s
t
r
u
cti
o
n
?
H
o
w
do
t
h
e
s
e
b
e
li
e
f
s
a
f
f
e
c
t
t
h
ei
r
c
l
as
s
r
o
o
m
p
r
a
c
t
i
c
e
s
?
ii)
To
w
h
a
t
d
e
g
r
e
e
do
t
h
e
s
e
t
e
a
c
h
er
s
p
e
r
c
e
i
v
e
t
h
e
n
ee
d
f
o
r
c
h
a
n
g
e
in
c
o
n
s
t
r
u
c
t
i
v
i
s
t
t
e
a
c
h
i
n
g
p
r
a
cti
c
e
s
?
iii)
W
h
a
t
c
o
n
d
i
ti
o
n
s
c
o
u
l
d
be
r
e
q
u
ir
e
d
to
e
n
c
o
u
r
a
g
e
c
o
n
s
t
r
u
c
t
i
v
is
t
p
r
a
c
t
i
c
es
?
2.
L
I
T
E
R
AT
U
RE
R
E
VI
E
W
2
.
1
.
E
ng
lis
h
t
ea
ching
a
nd
lea
rning
in
Viet
na
m
In
Vietn
am
,
C
o
n
f
u
cian
h
er
ita
g
e
cu
ltu
r
e
can
r
ein
f
o
r
ce
an
d
r
ep
r
esen
t
ex
is
tin
g
u
n
d
er
s
tan
d
i
n
g
s
of
t
h
e
teac
h
er
’
s
s
tatu
s
,
wo
r
k
,
an
d
th
e
teac
h
er
-
s
tu
d
e
n
t
r
elatio
n
s
h
ip
.
No
tab
ly
,
cu
ltu
r
al
ch
ar
ac
ter
is
t
ics
af
f
ec
t
teac
h
er
s
’
b
elief
s
ab
o
u
t
th
ei
r
wo
r
k
,
teac
h
er
-
s
tu
d
en
t
r
elatio
n
s
h
ip
s
,
class
r
o
o
m
m
ec
h
a
n
is
m
s
,
an
d
e
n
v
i
r
o
n
m
en
ts
,
so
t
h
ey
d
ir
ec
tly
af
f
ec
t
th
e
q
u
ality
of
t
h
eir
ed
u
ca
tio
n
[
9
]
–
[
1
1
]
.
B
ased
on
th
is
p
r
esu
m
p
ti
o
n
,
th
e
tea
ch
er
s
will
en
g
a
g
e
in
p
er
tin
en
t
b
eh
av
io
r
s
,
ac
tiv
ities
,
an
d
p
r
o
f
ess
io
n
al
ju
d
g
m
en
ts
t
h
at
will
lik
ely
im
p
ac
t
th
e
g
o
al
s
of
in
s
tr
u
ctio
n
an
d
lear
n
in
g
th
ey
wan
t
to
ac
h
ie
v
e
an
d
th
e
q
u
alities
of
class
r
o
o
m
q
u
ality
th
ey
wis
h
to
em
p
h
asize.
T
h
e
g
eo
g
r
a
p
h
ical
m
ak
eu
p
of
th
e
n
atio
n
an
d
th
e
way
of
life
of
th
e
Vietn
am
ese
p
eo
p
le
h
ad
an
im
p
ac
t
on
th
eir
in
d
ig
en
o
u
s
cu
ltu
r
e
,
wh
ic
h
a
s
s
im
ilated
an
d
m
o
d
if
ied
th
e
cu
ltu
r
al
id
ea
ls
of
C
o
n
f
u
cia
n
is
m
,
T
ao
is
m
,
an
d
B
u
d
d
h
is
m
o
v
e
r
th
e
m
o
r
e
th
a
n
a
th
o
u
s
an
d
y
ea
r
s
th
at
C
h
in
a
r
u
led
th
e
r
eg
i
o
n
[
1
2
]
–
[
1
4
]
.
Als
o
,
W
ester
n
id
ea
ls
h
av
e
af
f
ec
ted
i
n
d
ig
en
o
u
s
Vietn
am
ese
cu
ltu
r
e
th
r
o
u
g
h
Fre
n
ch
h
eg
em
o
n
y
,
Am
er
i
ca
n
in
v
asio
n
,
an
d
g
lo
b
aliza
tio
n
[
1
5
]
.
Sin
ce
C
o
n
f
u
cian
cu
ltu
r
e
an
d
teac
h
in
g
s
o
r
ig
in
ate
d
in
C
h
in
a,
th
e
Vietn
am
ese
h
av
e
d
e
m
o
n
s
tr
ated
f
r
eq
u
e
n
t
r
eg
a
r
d
f
o
r
k
n
o
wled
g
e
an
d
,
co
n
s
eq
u
en
tly
,
f
o
r
th
o
s
e
wh
o
s
u
p
p
ly
it,
also
k
n
o
wn
as
s
en
io
r
teac
h
er
s
or
teac
h
er
s
[
9
]
.
Kn
o
wled
g
e
is
r
eg
ar
d
ed
as
more
p
r
ec
io
u
s
th
an
wea
lth
m
ater
ials
b
ec
au
s
e
p
eo
p
le
b
eliev
e
th
at
k
n
o
wled
g
e
can
b
r
in
g
th
em
m
an
y
t
h
in
g
s
,
a
n
d
teac
h
er
s
a
r
e
a
ls
o
h
ig
h
ly
r
e
g
ar
d
e
d
as
th
e
s
ta
n
d
ar
d
“m
ir
r
o
r
”
of
a
m
o
r
al
teac
h
er
.
Du
r
in
g
th
at
p
er
io
d
,
n
u
m
e
r
o
u
s
Vietn
am
es
e
p
r
o
v
er
b
s
an
d
f
o
lk
tales
h
ig
h
ly
em
p
h
asize
th
e
im
p
o
r
tan
ce
of
teac
h
e
r
s
,
s
u
ch
as
“
Mộ
t
ch
ữ
là
Th
ầ
y,
n
ửa
ch
ữ
cũ
n
g
là
Th
ầ
y
”
(
On
e
wo
r
d
m
ay
m
ak
e
a
teac
h
er
;
ev
en
h
alf
a
wo
r
d
can
ac
co
m
p
lis
h
th
e
s
am
e
)
or
“
K
h
ô
n
g
Th
ầ
y,
đố
mà
y
là
m
n
ên
”
(
Yo
u
m
ay
do
n
o
th
in
g
with
o
u
t
teac
h
er
s
)
.
On
th
e
o
n
e
h
an
d
,
t
h
ese
id
ea
s
h
av
e
a
g
o
o
d
im
p
ac
t
on
e
d
u
ca
tio
n
,
p
a
r
ticu
lar
ly
t
h
e
d
y
n
a
m
ic
b
etwe
en
teac
h
er
s
an
d
s
tu
d
en
ts
.
On
th
e
o
th
er
h
an
d
,
r
esp
ec
t
f
o
r
k
n
o
wled
g
e
an
d
teac
h
er
s
m
o
tiv
ate
p
e
o
p
le
to
lear
n
by
all
m
ea
n
s
an
d
s
tim
u
late
p
u
p
ils
’
m
o
tiv
atio
n
a
n
d
p
ass
io
n
f
o
r
lear
n
in
g
.
H
o
w
e
v
e
r
,
a
c
c
o
r
d
i
n
g
to
V
y
g
o
t
s
k
y
’
s
t
h
e
o
r
y
of
s
o
c
i
a
l
c
o
n
s
t
r
u
c
t
i
v
is
m
,
s
u
c
h
a
r
e
l
a
t
i
o
n
s
h
i
p
m
a
y
h
i
n
d
e
r
t
h
e
d
e
v
e
l
o
p
m
e
n
t
of
l
e
a
r
n
e
r
s
’
s
o
c
i
al
s
k
i
l
ls
,
c
r
e
a
ti
v
i
t
y
,
c
o
l
l
a
b
o
r
a
t
i
o
n
,
c
o
m
m
u
n
i
c
at
i
o
n
,
a
n
d
c
r
i
t
i
c
al
t
h
i
n
k
i
n
g
s
k
i
l
ls
[
1
6
]
.
In
s
u
c
h
a
w
a
y
,
p
u
p
i
ls
h
a
v
e
g
r
a
d
u
a
l
l
y
b
e
c
o
m
e
p
a
s
s
i
v
e
a
n
d
o
b
e
d
i
e
n
t
l
is
t
e
n
e
r
s
w
h
o
o
n
l
y
h
e
a
r
a
n
d
do
not
c
o
n
t
r
i
b
u
t
e
to
t
h
e
c
o
o
p
e
r
a
t
i
v
e
a
n
d
i
n
te
r
a
c
t
i
o
n
t
as
k
[
1
7
]
.
T
ea
ch
in
g
an
d
s
tu
d
y
in
g
E
n
g
l
is
h
at
all
lev
el
s
h
as
b
ee
n
“a
d
ilem
m
a
f
ac
in
g
r
ec
en
t
Vi
etn
am
ese
g
o
v
er
n
m
en
ts
”
[
1
8
]
s
in
ce
E
n
g
lis
h
was
ad
d
ed
to
th
e
n
atio
n
al
cu
r
r
icu
lu
m
.
Fo
r
a
v
e
r
y
lo
n
g
p
er
io
d
,
E
n
g
lis
h
lan
g
u
ag
e
in
s
tr
u
ctio
n
(
E
L
T
)
h
a
s
f
av
o
r
e
d
th
e
g
r
am
m
ar
-
t
r
an
s
latio
n
tech
n
i
q
u
e,
in
w
h
ich
“tea
c
h
er
s
an
d
tex
tb
o
o
k
s
ar
e
co
n
s
id
er
ed
a
u
th
o
r
itativ
e
s
o
u
r
ce
s
of
k
n
o
wled
g
e”
[
1
9
]
.
H
o
wev
er
,
b
ec
a
u
s
e
g
r
am
m
ar
an
d
v
o
ca
b
u
lar
y
ar
e
th
e
p
r
im
ar
y
a
r
ea
s
of
co
n
ce
n
tr
atio
n
in
E
n
g
lis
h
lan
g
u
ag
e
i
n
s
tr
u
ctio
n
,
lan
g
u
ag
e
is
tr
ea
ted
m
o
r
e
lik
e
a
s
tu
d
y
s
u
b
ject
th
an
a
to
o
l
f
o
r
e
f
f
icien
t
c
o
m
m
u
n
icatio
n
[
2
0
]
.
T
h
is
co
n
v
en
tio
n
al
m
em
o
r
y
-
b
ased
m
et
h
o
d
of
teac
h
i
n
g
E
n
g
lis
h
“o
f
ten
m
ak
es
no
s
en
s
e
in
co
n
tex
t
an
d
is
p
r
ef
er
r
ed
o
v
er
m
e
an
in
g
f
u
l
c
o
m
m
u
n
icatio
n
”
[
2
0
]
.
T
h
is
s
ettin
g
d
o
es
not
s
tr
o
n
g
ly
em
p
h
asize
th
e
v
a
lu
e
of
cu
ltu
r
al
ed
u
ca
tio
n
.
Oth
er
f
ac
to
r
s
also
c
o
n
tr
ib
u
te
d
to
Vietn
am
’
s
p
r
o
b
lem
s
with
teac
h
in
g
an
d
lea
r
n
in
g
.
First,
in
an
E
FL
s
ettin
g
,
s
tu
d
en
ts
ar
e
lim
ited
to
u
s
in
g
E
n
g
lis
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Seco
n
d
,
lea
r
n
er
s
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with
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p
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in
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ten
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k
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due
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eth
o
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2
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J
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1438
teac
h
er
s
’
lack
of
ex
p
er
ien
ce
,
a
n
d
r
estricte
d
E
n
g
lis
h
class
es
[
2
1
]
,
[
2
2
]
.
Af
ter
m
an
y
y
ea
r
s
of
lear
n
in
g
E
n
g
lis
h
at
s
ch
o
o
ls
,
Vietn
am
ese
lear
n
er
s
“c
an
n
o
t
u
s
e
ev
en
s
im
p
le
s
en
ten
ce
s
f
o
r
co
m
m
u
n
icatio
n
p
u
r
p
o
s
es”
[
2
2
]
.
In
th
is
ca
s
e,
th
ey
m
ay
be
s
u
cc
ess
f
u
l
u
s
er
s
of
g
r
am
m
a
r
an
d
v
o
ca
b
u
lar
y
but
n
ee
d
m
o
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e
co
n
f
i
d
en
c
e
wh
en
s
p
ea
k
in
g
to
f
o
r
eig
n
e
r
s
[
2
3
]
.
Desp
ite
t
h
e
V
ietn
am
Min
is
tr
y
o
f
E
d
u
ca
tio
n
an
d
T
r
ain
in
g
r
em
ar
k
ab
le
atte
m
p
ts
,
it
is
b
eliev
ed
th
at
E
n
g
lis
h
ed
u
ca
tio
n
in
th
e
Vietn
am
ese
co
n
tex
t
h
as
y
et
to
liv
e
up
to
th
e
ex
p
ec
tatio
n
s
of
p
o
licy
m
ak
er
s
an
d
p
u
p
ils
[
2
4
]
.
T
h
e
f
u
n
d
am
en
tal
o
b
jectiv
es
of
th
e
n
atio
n
al
p
r
o
g
r
am
h
av
e
n
o
t
b
ee
n
m
et
by
E
n
g
lis
h
ed
u
ca
tio
n
in
th
e
Vietn
am
ese
s
ettin
g
with
o
u
t
co
n
s
id
er
ab
le
r
ev
is
io
n
s
an
d
im
p
r
o
v
em
e
n
ts
in
th
e
cu
r
r
icu
lu
m
.
T
h
e
s
tan
d
ar
d
of
teac
h
in
g
an
d
s
tu
d
y
in
g
f
o
r
eig
n
lan
g
u
ag
es
m
u
s
t
s
till
s
atis
f
y
th
e
n
ee
d
s
of
th
e
n
atio
n
’
s
g
r
o
wth
[
2
5
]
.
2
.
2
.
Co
ns
t
ruct
iv
is
t
t
ea
ching
C
o
n
s
tr
u
ctiv
is
m
h
as
b
ee
n
r
eg
ar
d
ed
as
“a
p
o
wer
f
u
l
f
o
r
ce
in
l
an
g
u
ag
e
e
d
u
ca
tio
n
”
an
d
h
as
r
em
ar
k
ab
ly
b
ec
o
m
e
th
e
lead
in
g
th
e
o
r
etica
l
v
iew
in
t
h
e
f
ield
of
ed
u
ca
ti
o
n
in
n
o
v
atio
n
[
2
6
]
,
[
2
7
]
.
It
is
ac
k
n
o
wled
g
e
d
th
at
co
n
s
tr
u
ctiv
is
m
p
r
o
v
id
es
“a
lo
g
ical
an
d
a
u
s
ef
u
l
f
r
am
ewo
r
k
f
o
r
c
o
m
p
r
eh
en
d
in
g
an
d
in
ter
p
r
etin
g
teac
h
i
n
g
an
d
lear
n
in
g
e
v
en
ts
.
”
T
h
is
m
o
d
el
u
s
es
co
n
s
tr
u
ctiv
is
m
“to
co
n
s
tr
u
ct
a
class
r
o
o
m
th
at
m
a
y
m
ax
im
ize
p
u
p
ils
’
p
er
f
o
r
m
an
ce
”
[
2
8
]
.
T
h
e
co
m
m
u
n
ity
s
h
o
u
l
d
p
r
o
v
id
e
th
e
a
tm
o
s
p
h
er
e,
d
if
f
icu
lties
,
an
d
s
u
p
p
o
r
t
r
eq
u
ir
e
d
to
p
r
o
m
o
te
m
ath
em
atica
l
cr
ea
tio
n
”
[
2
9
]
.
T
ea
c
h
er
s
’
id
ea
s
ab
o
u
t
teac
h
in
g
a
n
d
lear
n
in
g
will
eit
h
er
h
elp
or
im
p
ed
e
th
e
ad
o
p
tio
n
of
in
n
o
v
ativ
e
cu
r
r
icu
la
[
3
0
]
.
T
h
u
s
,
ass
ess
in
g
an
d
ad
d
r
ess
in
g
teac
h
er
s
’
in
tellectu
al
an
d
p
ed
ag
o
g
ical
v
iews
is
cr
u
cia
l
b
ef
o
r
e
th
e
r
e
f
o
r
m
attem
p
t
.
Fig
u
r
e
1
illu
s
tr
ates
th
e
c
o
n
n
ec
tio
n
b
etwe
en
ed
u
ca
tio
n
al
v
iews,
ep
is
tem
o
lo
g
ical
b
elief
s
,
an
d
th
e
ap
p
licati
o
n
of
CT
ap
p
r
o
a
ch
es.
Acc
o
r
d
in
g
to
p
r
ev
io
u
s
s
tu
d
ies,
teac
h
er
s
’
e
p
is
tem
o
lo
g
ical
id
ea
s
ab
o
u
t
k
n
o
wled
g
e
m
ig
h
t
i
m
p
ac
t
th
eir
teac
h
in
g
s
tr
ateg
ies
an
d
less
o
n
p
r
ep
ar
atio
n
[
3
0
]
.
Den
g
et
a
l.
[
3
1
]
ass
er
t
ed
th
at
ac
ad
em
ics
s
h
o
u
ld
p
a
y
p
ar
ticu
la
r
atten
tio
n
to
teac
h
er
s
’
p
er
ce
iv
ed
b
elief
s
b
y
f
o
cu
s
in
g
o
n
k
n
o
wled
g
e
d
ev
elo
p
m
en
t
in
th
e
p
r
esen
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ed
u
ca
tio
n
al
r
ef
o
r
m
e
n
v
ir
o
n
m
en
t.
T
h
e
in
n
o
v
atio
n
-
d
r
iv
en
cu
r
r
ic
u
lu
m
r
e
q
u
ir
es
a
co
n
s
tr
u
ctiv
is
t
ep
is
te
m
o
lo
g
y
th
at
v
iews
k
n
o
wled
g
e
as
b
u
ilt
o
n
c
o
n
tex
t
u
al
in
f
o
r
m
atio
n
an
d
p
er
s
o
n
al
ex
p
er
ien
ce
s
.
A
f
u
r
th
e
r
co
n
v
en
tio
n
al
ap
p
r
o
ac
h
to
ed
u
ca
tio
n
is
th
at
i
n
f
o
r
m
atio
n
is
im
p
ar
ted
to
p
u
p
ils
b
y
ex
p
e
r
ien
ce
d
teac
h
e
r
s
an
d
s
u
b
ject
m
atter
ex
p
er
ts
[
3
1
]
.
T
h
er
e
is
litt
le
d
o
u
b
t th
at
teac
h
er
s
’
p
er
s
p
ec
tiv
es o
n
k
n
o
wled
g
e
in
f
lu
en
ce
th
ei
r
teac
h
in
g
.
2
.
3
.
E
du
ca
t
io
na
l c
ha
ng
e
C
o
m
b
in
in
g
th
e
ch
a
n
g
e
s
ty
le
in
d
icato
r
(
C
SI)
b
y
M
u
s
s
elwh
it
e
an
d
I
n
g
r
am
[
3
2
]
with
th
r
ee
co
n
ce
p
tu
a
l
f
r
am
ewo
r
k
s
,
in
clu
d
in
g
W
en
g
er
[
3
3
]
t
h
eo
r
y
o
f
co
m
m
u
n
itie
s
o
f
p
r
ac
tice
(
C
OP)
,
co
m
p
le
x
ad
ap
tiv
e
s
y
s
tem
s
(
C
AS)
b
y
Stacey
[
3
4
]
,
an
d
F
u
llan
[
3
5
]
t
h
eo
r
y
o
f
ed
u
ca
tio
n
al
ch
an
g
e
(
T
E
C
)
,
p
r
o
v
id
ed
a
co
m
p
r
eh
e
n
s
iv
e
an
d
in
-
d
ep
th
b
asis
f
o
r
u
n
d
er
s
tan
d
in
g
th
e
tr
an
s
f
o
r
m
atio
n
o
f
ed
u
ca
tio
n
in
th
e
co
n
tex
t
o
f
C
T
in
Vietn
am
’
s
h
ig
h
s
ch
o
o
ls
.
T
h
e
s
tu
d
y
’
s
h
y
p
o
t
h
e
s
es
o
f
ed
u
ca
tio
n
al
r
ef
o
r
m
a
r
e
s
h
o
wn
in
T
ab
le
1
,
wh
ich
r
e
v
ea
ls
h
o
w
ess
en
tial
f
ac
to
r
s
in
ter
ac
t
i
n
ch
a
n
g
in
g
t
h
in
g
s
.
Ad
d
itio
n
ally
,
t
h
ey
h
ig
h
lig
h
t
th
e
cir
c
u
m
s
tan
ce
s
m
o
s
t
lik
ely
to
e
n
co
u
r
ag
e
lo
n
g
-
ter
m
ed
u
ca
tio
n
al
r
ef
o
r
m
in
C
T
s
ec
o
n
d
ar
y
s
ch
o
o
ls
in
Vietn
am
.
Fig
u
r
e
1.
T
h
e
r
elatio
n
s
h
ip
b
et
wee
n
teac
h
er
s
’
b
elief
s
,
an
d
th
e
u
s
e
of
CT
T
ab
le
1.
T
h
eo
r
ies
of
e
d
u
ca
tio
n
al
ch
an
g
e
(
E
C
)
u
s
ed
in
th
e
s
tu
d
y
Th
e
o
r
i
e
s
o
f
E
C
A
i
ms
I
mp
l
i
c
a
t
i
o
n
s
1
.
Th
e
t
h
e
o
r
y
o
f
c
o
m
p
l
e
x
a
d
a
p
t
i
v
e
sy
st
e
ms (
C
A
S
)
[
3
4
]
-
To
c
o
mm
u
n
i
c
a
t
e
t
h
e
r
e
q
u
i
r
e
me
n
t
o
f
v
i
e
w
i
n
g
e
d
u
c
a
t
i
o
n
a
l
t
r
a
n
sf
o
r
ma
t
i
o
n
a
s
a
m
u
l
t
i
f
a
c
e
t
e
d
p
r
o
c
e
ss.
-
To
s
u
c
c
e
e
d
,
c
h
a
n
g
e
l
e
a
d
e
r
s
n
e
e
d
t
o
u
n
d
e
r
st
a
n
d
t
h
e
n
e
c
e
ss
a
r
y
s
o
c
i
a
l
a
n
d
c
o
n
t
e
x
t
u
a
l
c
o
n
d
i
t
i
o
n
s
t
o
b
a
l
a
n
c
e
n
e
w
b
e
h
a
v
i
o
r
p
a
t
t
e
r
n
s.
2
.
F
u
l
l
a
n
’
s
t
h
e
o
r
y
o
f
e
d
u
c
a
t
i
o
n
a
l
c
h
a
n
g
e
(
TEC
)
[
3
5
]
-
To
c
l
a
r
i
f
y
,
a
n
y
t
r
a
n
sf
o
r
ma
t
i
o
n
i
n
e
d
u
c
a
t
i
o
n
mu
st
“
s
t
r
u
g
g
l
e
d
i
r
e
c
t
l
y
w
i
t
h
e
x
i
st
i
n
g
c
u
l
t
u
r
e
s
i
n
w
h
i
c
h
n
e
w
v
a
l
u
e
s
a
n
d
p
r
a
c
t
i
c
e
s
ma
y
b
e
r
e
q
u
i
r
e
d
.
”
-
Th
i
s
p
e
r
sp
e
c
t
i
v
e
ma
y
f
o
c
u
s
o
n
b
r
i
n
g
i
n
g
a
b
o
u
t
a
t
r
a
n
sf
o
r
ma
t
i
o
n
a
l
e
d
u
c
a
t
i
o
n
a
l
s
h
i
f
t
i
n
p
e
d
a
g
o
g
i
c
a
l
c
u
l
t
u
r
e
r
e
g
a
r
d
i
n
g
b
e
h
a
v
i
o
r
a
n
d
b
e
l
i
e
f
s
.
3
.
W
e
n
g
e
r
’
s
t
h
e
o
r
y
o
f
c
o
mm
u
n
i
t
i
e
s
o
f
p
r
a
c
t
i
c
e
(
T
C
P
)
[
3
3
]
-
TC
P
serv
e
s
a
s
a
r
e
p
o
si
t
o
r
y
f
o
r
k
n
o
w
l
e
d
g
e
g
e
n
e
r
a
t
i
o
n
,
sh
a
r
i
n
g
,
a
n
d
d
e
v
e
l
o
p
me
n
t
,
o
f
f
e
r
i
n
g
o
p
p
o
r
t
u
n
i
t
i
e
s
f
o
r
i
n
n
o
v
a
t
i
o
n
.
-
I
t
i
s
i
m
p
e
r
a
t
i
v
e
t
o
c
o
n
s
i
d
e
r
e
d
u
c
a
t
i
o
n
a
l
e
st
a
b
l
i
s
h
me
n
t
s
s
u
c
h
a
s
s
o
c
i
a
l
i
n
s
t
i
t
u
t
i
o
n
s
t
h
a
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[
3
6
]
In
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d
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e
q
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tech
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iq
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[
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[
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e.
g
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tech
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Hew
s
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[4
2
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.
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v
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ata
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co
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m
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id
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s
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eth
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.
T
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en
,
th
e
o
b
s
er
v
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ata
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aly
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to
u
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e
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s
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teac
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class
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m
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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[
4
3
]
.
T
h
is
was
d
o
n
e
to
ch
ec
k
f
o
r
in
d
iv
i
d
u
al
a
n
d
co
llectiv
e
class
r
o
o
m
b
eh
av
io
r
p
atter
n
s
an
d
how
th
e
y
co
n
n
ec
ted
to
teac
h
er
s
’
ex
p
r
ess
ed
v
iews
[
4
4
]
.
T
h
e
s
tim
u
lated
r
ec
all
in
ter
v
iews
wer
e
ev
alu
ated
to
u
n
d
er
s
tan
d
th
e
f
u
n
d
am
e
n
tal
ca
u
s
es
of
t
ea
ch
er
s
’
class
r
o
o
m
b
eh
av
io
r
.
T
h
is
was
ac
co
m
p
lis
h
ed
by
id
en
tify
i
n
g
th
e
wo
r
d
s
an
d
p
h
r
ases
th
at
ce
r
tain
teac
h
er
s
u
tili
ze
d
.
Af
ter
th
at,
p
atter
n
s
wer
e
ca
r
e
f
u
lly
c
h
o
s
en
in
to
b
r
o
a
d
ca
teg
o
r
ies
to
m
atch
th
e
s
tu
d
y
’
s
r
esear
ch
ai
m
s
[
4
5
]
.
T
h
e
b
r
o
ad
ca
teg
o
r
ies
r
elev
an
t
to
teac
h
er
s
’
b
elief
s
in
CT
f
o
r
th
e
cu
r
r
e
n
t
r
esear
ch
in
clu
d
e,
f
o
r
ex
am
p
le,
k
n
o
wled
g
e
is
co
n
s
tr
u
cted
,
m
o
tiv
atio
n
is
v
ital to
lear
n
in
g
,
teac
h
er
’
s
r
o
les,
an
d
lear
n
er
s
’
r
o
les.
T
h
er
e
wer
e
s
u
b
g
r
o
u
p
s
b
en
ea
th
each
of
th
ese
m
ajo
r
ca
teg
o
r
ies.
Fo
r
i
n
s
tan
ce
,
in
th
e
ca
teg
o
r
y
“
m
o
tiv
atio
n
is
v
ital
to
lear
n
in
g
,
”
th
er
e
wer
e
s
u
b
-
ca
teg
o
r
ies
s
u
ch
as
“
lear
n
in
g
to
p
ass
th
e
ex
am
”
or
“
lear
n
in
g
f
o
r
g
o
o
d
m
a
r
k
s
.
”
T
h
is
s
tu
d
y
u
s
ed
MA
XQDA
f
o
r
d
ata
an
aly
s
is
[
4
6
]
to
r
e
d
u
c
e
tim
e
an
d
f
ac
ilit
ate
th
e
o
r
g
an
izatio
n
an
d
r
etr
iev
al
of
co
d
e
d
d
ata.
All
d
ata
s
o
u
r
ce
s
f
r
o
m
th
e
o
b
s
er
v
atio
n
s
an
d
in
ter
v
iews
wer
e
g
iv
en
to
MA
XQDA
.
By
u
s
in
g
MA
XQDA
to
co
d
e
th
e
d
ata,
th
e
r
esear
ch
er
s
f
o
u
n
d
it
ea
s
ier
to
an
aly
ze
th
e
ca
s
es.
Af
ter
co
d
in
g
th
e
d
ata
f
o
r
a
s
in
g
le
p
ar
ticip
an
t,
th
e
r
esear
ch
er
s
q
u
alitativ
ely
a
n
aly
ze
d
th
at
p
er
s
o
n
’
s
d
ata.
W
h
ile
co
d
in
g
,
th
e
r
esear
ch
er
s
to
o
k
n
o
tes
on
an
al
y
tical
p
o
in
ts
or
p
ar
ag
r
a
p
h
s
to
in
clu
d
e
in
th
e
r
ep
o
r
t
later
,
as
s
h
o
wn
in
Fig
u
r
e
3,
wh
ich
d
ep
icts
an
ex
am
p
le
of
t
h
e
in
itial
co
d
es
of
teac
h
er
s
’
an
d
p
u
p
ils
’
r
o
les
th
at
em
er
g
ed
f
r
o
m
th
e
o
b
s
er
v
atio
n
d
ata,
wh
ich
h
el
p
ed
th
e
r
esear
ch
er
s
s
y
n
th
esize
an
d
a
n
aly
ze
th
e
d
ata
q
u
ick
l
y
an
d
s
y
s
tem
atica
lly
.
Fig
u
r
e
3.
I
n
itial
co
d
es
of
teac
h
er
s
’
an
d
p
u
p
ils
’
r
o
les
f
r
o
m
th
e
o
b
s
er
v
atio
n
d
ata
Af
ter
h
av
in
g
in
itial
co
d
es
attu
n
ed
to
t
h
e
ten
ets
o
f
C
T
,
th
e
r
esear
ch
er
s
s
ea
r
ch
ed
f
o
r
s
im
ilar
ities
an
d
d
if
f
er
en
ce
s
am
o
n
g
th
o
s
e
co
d
e
s
.
Nex
t,
u
n
d
er
ap
p
r
o
p
r
iate
p
r
i
o
r
th
em
es,
th
e
r
esear
ch
er
s
ca
teg
o
r
ized
th
e
r
elev
an
t
co
d
e
ch
u
n
k
s
,
s
u
ch
as
k
ey
wo
r
d
s
o
r
p
h
r
ases
in
t
h
e
in
ter
v
iews
an
d
r
ele
v
an
t
e
p
is
o
d
es
o
f
th
e
o
b
s
er
v
atio
n
d
ata.
Fin
ally
,
th
e
r
esear
c
h
er
s
co
n
s
tr
u
cted
th
e
th
em
es
with
t
h
eir
e
m
er
g
en
t
s
u
b
-
th
em
es
f
r
o
m
th
o
s
e
p
iece
s
o
f
c
o
d
e,
as
s
h
o
wn
in
T
ab
les 3
a
n
d
4
.
Af
ter
co
m
p
letin
g
all
tr
an
s
cr
ip
tio
n
an
d
co
d
in
g
,
t
h
is
s
tu
d
y
co
n
d
u
cte
d
a
q
u
alitativ
e
an
aly
s
is
o
f
ea
ch
p
ar
ticip
an
t’
s
s
em
i
-
s
tr
u
ctu
r
ed
,
o
b
s
er
v
atio
n
al,
a
n
d
f
lash
b
ac
k
in
ter
v
iews.
Acc
o
r
d
in
g
to
Patto
n
[
4
7
]
,
“c
ase
an
aly
s
is
in
clu
d
es
ar
r
an
g
in
g
d
a
ta
b
y
s
p
ec
if
ic
ca
s
es
f
o
r
e
x
ten
s
iv
e
in
v
esti
g
atio
n
an
d
c
o
m
p
ar
is
o
n
.
”
A
n
in
itial
s
tep
in
co
m
p
ar
in
g
in
s
tan
ce
s
is
to
a
n
aly
ze
th
e
d
ata
f
o
r
ea
c
h
ca
s
e.
B
ef
o
r
e
th
e
ex
am
p
les
ar
e
g
r
o
u
p
ed
b
y
s
u
b
ject
in
an
in
d
u
ctiv
e
tech
n
iq
u
e,
th
e
r
esear
ch
er
s
m
ig
h
t
g
en
e
r
ate
in
d
iv
i
d
u
al
in
s
tan
ce
s
to
c
o
n
ce
n
tr
ate
o
n
a
n
d
th
o
r
o
u
g
h
l
y
co
m
p
r
eh
e
n
d
ea
ch
ca
s
e
[
4
7
]
.
C
ase
-
by
-
ca
s
e
an
aly
s
is
aid
s
in
id
en
tif
y
in
g
t
h
e
th
em
es
a
n
d
p
atter
n
s
th
at
lin
k
v
ar
io
u
s
ev
en
ts
[
4
7
]
.
T
h
en
,
a
t
en
-
to
-
f
if
tee
n
-
p
ag
e
r
e
p
o
r
t
was
wr
itten
f
o
r
ea
ch
p
ar
ticip
an
t
in
th
e
ca
s
e
s
tu
d
y
th
at
in
clu
d
ed
r
i
g
o
r
o
u
s
an
aly
s
is
o
f
a
ll d
ata
f
o
r
th
e
p
ar
ticip
an
ts
.
T
ab
le
3.
A
s
am
p
le
of
s
ea
r
ch
in
g
th
em
es
f
r
o
m
th
e
in
ter
v
iew
d
ata
Ex
c
e
r
p
t
s
Th
e
m
e
s
a
n
d
s
u
b
-
t
h
e
m
e
s
W
i
l
l
i
n
g
n
e
ss
[
a
n
d
]
g
e
t
t
i
n
g
p
u
p
i
l
s
i
n
v
o
l
v
e
d
in
t
h
e
l
e
ss
o
n
a
r
e
i
m
p
o
r
t
a
n
t
[
i
n
l
e
a
r
n
i
n
g
E
n
g
l
i
s
h
]
[
T6
.
I
1
.
2
2
]
-
M
o
t
i
v
a
t
i
o
n
l
e
a
r
n
i
n
g
I
t
h
i
n
k
g
i
v
i
n
g
p
u
p
i
l
s
p
r
a
c
t
i
c
a
l
e
x
p
e
r
i
e
n
c
e
s
b
o
o
st
s
l
e
a
r
n
i
n
g
[
T7
.
I
1
.
1
3
]
-
A
u
t
h
e
n
t
i
c
l
e
a
r
n
i
n
g
Th
e
y
sh
o
u
l
d
a
c
t
i
v
e
l
y
i
n
t
e
r
a
c
t
in
p
a
i
r
s/
g
r
o
u
p
s,
a
n
d
c
o
n
t
r
i
b
u
t
e
i
d
e
a
s
to
h
e
l
p
i
m
p
r
o
v
e
t
h
e
i
r
c
o
mm
u
n
i
c
a
t
i
o
n
c
o
mp
e
t
e
n
c
e
.
[
T
6
.
I
1
.
1
2
]
-
Th
e
r
o
l
e
of
l
e
a
r
n
e
r
s
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t
J
E
v
al
&
R
es E
d
u
c
I
SS
N:
2252
-
8
8
2
2
A
q
u
a
lita
tive
ca
s
e
s
tu
d
y
o
f c
o
n
s
tr
u
ctivi
s
t te
a
ch
in
g
a
t a
h
ig
h
s
ch
o
o
l in
a
n
o
r
th
ern
…
(
P
h
a
m
Th
i Ki
eu
Oa
n
h
)
1441
T
ab
le
4.
A
s
am
p
le
of
s
ea
r
ch
in
g
th
em
es
f
r
o
m
th
e
o
b
s
er
v
atio
n
d
ata
C
l
a
s
sr
o
o
m
o
b
serv
a
t
i
o
n
t
r
a
n
scri
p
t
a
n
d
f
i
e
l
d
n
o
t
e
s
Th
e
m
e
s
a
n
d
s
u
b
-
t
h
e
m
e
s
o
f
c
o
l
l
a
b
o
r
a
t
i
o
n
l
e
a
r
n
i
n
g
i)
A
f
t
e
r
t
h
e
g
r
o
u
p
f
i
n
i
s
h
e
d
[
p
r
e
se
n
t
i
n
g
t
h
e
g
r
o
u
p
’
s
w
o
r
k
]
,
T
6
e
n
c
o
u
r
a
g
e
d
t
h
e
o
t
h
e
r
g
r
o
u
p
s t
o
a
sk
q
u
e
st
i
o
n
s.
“
H
o
w
ma
n
y
t
i
mes
d
i
d
t
h
e
t
e
a
c
h
e
r
a
sk
t
h
e
g
r
o
u
p
s
?
”
i)
En
c
o
u
r
a
g
i
n
g
t
h
e
g
r
o
u
p
s
t
o
g
i
v
e
f
e
e
d
b
a
c
k
t
o
t
h
e
p
r
e
se
n
t
i
n
g
g
r
o
u
p
ii)
Th
e
f
o
u
r
t
h
g
r
o
u
p
mem
b
e
r
t
h
a
n
k
e
d
a
n
d
a
n
sw
e
r
e
d
t
h
e
q
u
e
st
i
o
n
.
Th
e
n
,
t
h
e
w
h
o
l
e
c
l
a
s
s
a
p
p
l
a
u
d
e
d
t
h
e
g
r
o
u
p
.
ii)
R
e
s
p
o
n
d
i
n
g
t
o
a
q
u
e
st
i
o
n
(
a
g
r
o
u
p
)
iii)
T6
a
d
d
e
d
s
o
m
e
e
x
p
l
a
n
a
t
i
o
n
s f
o
r
t
h
e
a
n
sw
e
r
s
t
h
e
g
r
o
u
p
h
a
s
g
i
v
e
n
.
iii)
C
l
a
r
i
f
y
i
n
g
a
n
sw
e
r
s
i
v
)
G
r
o
u
p
s
w
e
r
e
i
n
v
i
t
e
d
t
o
s
u
b
mi
t
t
h
e
o
u
t
c
o
mes
o
f
t
h
e
i
r
c
o
n
v
e
r
sa
t
i
o
n
b
y
T
6
.
Th
e
f
i
r
st
-
r
o
w
g
r
o
u
p
w
a
s
g
i
v
e
n
,
b
u
t
i
t
w
a
s
n
o
t
y
e
t
p
r
e
p
a
r
e
d
.
H
e
r
e
p
e
a
t
e
d
l
y
i
n
q
u
i
r
e
d
a
b
o
u
t
t
h
e
i
r
r
e
a
d
i
n
e
ss.
i
v
)
O
f
f
e
r
i
n
g
a
n
d
a
p
p
o
i
n
t
i
n
g
g
r
o
u
p
s
t
o
p
r
e
se
n
t
4.
RE
SU
L
T
S
AND
D
I
SCU
SS
I
O
N
4
.
1
.
F
ind
ing
s
a
nd
dis
cu
s
s
io
n
s
f
o
r
re
s
ea
rc
h ques
t
io
n
1
4
.
1
.
1
.
T
hem
e
1:
t
e
a
cher
s
’
belief
s
a
nd
t
heir
a
ct
ua
l pra
ct
ices a
bo
ut
pre
-
ex
is
t
ing
k
no
wledg
e
It
can
be
ch
allen
g
in
g
to
e
x
tr
ac
t
lear
n
er
s
’
p
ast
n
o
tio
n
s
an
d
u
tili
ze
th
em
to
g
en
er
ate
n
ew
o
n
e
s
b
ec
au
s
e
T
C
s
an
d
NPs
h
esit
ated
to
do
s
o
.
On
th
e
o
th
er
h
a
n
d
,
th
e
AOs
ar
e
ad
am
an
t
th
at
it
is
cr
u
cial
to
elicit
p
r
io
r
in
f
o
r
m
atio
n
f
r
o
m
s
tu
d
en
ts
b
ec
au
s
e
th
ey
u
n
d
er
s
tan
d
th
at
k
n
o
wled
g
e
is
b
est
ac
q
u
ir
ed
an
d
co
n
s
tr
u
cted
th
r
o
u
g
h
p
r
ev
io
u
s
lea
r
n
in
g
.
E
v
e
n
m
o
r
e
u
n
ex
p
ec
te
d
ly
,
t
h
e
T
C
s
ex
p
r
es
s
ed
co
n
ce
r
n
th
at
r
ev
iewin
g
th
e
p
ast
less
o
n
wo
u
ld
tak
e
to
o
lo
n
g
a
n
d
th
at
th
e
s
tu
d
en
ts
(
Ss
)
wo
u
l
d
o
n
ly
s
o
m
etim
es
r
em
em
b
e
r
wh
at
th
ey
alr
e
ad
y
k
n
ew.
Simp
ly
tr
an
s
f
er
r
in
g
th
eir
id
ea
s
to
t
h
e
p
u
p
ils
was
th
e
p
o
p
u
lar
teac
h
in
g
m
eth
o
d
f
o
r
t
h
e
T
C
s
an
d
NPs
,
wh
o
h
a
v
e
d
if
f
er
en
t
teac
h
in
g
s
tr
ateg
ies,
ev
en
if
th
ey
b
o
t
h
b
eliev
e
in
p
r
io
r
k
n
o
wled
g
e
.
W
h
ile
th
e
T
C
s
ig
n
o
r
ed
r
ec
allin
g
s
tu
d
en
ts
’
ex
p
er
ie
n
ce
s
,
one
NP
ex
p
lain
ed
n
ew
t
o
p
ics
to
t
h
e
l
ea
r
n
er
s
th
r
o
u
g
h
d
r
awin
g
s
an
d
d
iag
r
am
s
.
T
h
ey
d
id
not
u
s
e
ex
am
p
les
f
r
o
m
th
eir
ar
ea
to
illu
s
tr
ate
th
e
id
ea
s
.
W
h
ile
one
NP
u
s
ed
in
s
tan
ce
s
f
r
o
m
o
r
d
in
ar
y
life
to
in
tr
o
d
u
ce
n
ew
co
n
ce
p
ts
to
th
e
class
,
th
e
r
esear
ch
er
s
f
o
u
n
d
t
h
at
m
o
s
t
p
u
p
ils
co
u
ld
not
o
f
f
e
r
th
eir
in
s
tan
ce
s
of
th
e
to
p
ics,
a
n
d
m
o
s
t
p
u
p
ils
s
o
u
g
h
t
u
n
d
e
r
s
tan
d
in
g
f
r
o
m
th
ei
r
teac
h
er
s
.
T
h
is
r
em
ar
k
alig
n
s
with
th
e
f
i
n
d
in
g
s
of
th
e
2
0
0
3
-
2
0
0
7
Actio
n
Plan
r
e
p
o
r
ts
,
wh
ich
p
o
in
ted
o
u
t
a
teac
h
er
-
ce
n
ter
e
d
ap
p
r
o
ac
h
a
n
d
a
lack
of
en
g
a
g
em
en
t.
T
h
e
p
ap
er
s
also
s
u
g
g
ested
t
h
at
co
n
v
e
n
tio
n
al
s
cien
tific
in
s
tr
u
ctio
n
in
Vietn
am
ese
h
ig
h
s
ch
o
o
ls
d
o
es
not
co
n
n
ec
t
p
u
p
ils
’
ex
is
tin
g
k
n
o
wled
g
e,
ab
ilit
ies,
an
d
in
ter
ests
to
n
ew
o
n
es
[
4
8
]
.
T
h
e
r
esea
r
ch
er
s
o
b
s
er
v
e
d
th
at
“m
o
s
t
s
tu
d
en
ts
in
th
e
AOs’
less
o
n
co
u
ld
f
o
r
ec
ast
r
esu
lts
an
d
u
s
e
r
ea
l
-
wo
r
ld
ex
am
p
les
to
clar
if
y
n
ew
co
n
ce
p
ts
.
”
In
b
r
ief
,
ev
en
th
o
u
g
h
all
of
t
h
e
teac
h
e
r
s
in
t
h
e
r
esear
ch
h
ad
a
g
en
er
ally
f
av
o
r
ab
le
b
elief
to
war
d
p
r
io
r
k
n
o
wled
g
e
,
th
er
e
a
r
e
th
r
ee
d
if
f
er
en
t
g
r
o
u
p
s
wh
er
e
t
h
e
t
ea
ch
er
s
’
ac
tu
al
b
eh
a
v
io
r
d
iv
er
g
ed
d
r
a
m
atica
lly
.
4
.
1
.
2
.
T
hem
e
2:
t
e
a
cher
s
’
belief
s
a
nd
t
heir
a
ct
ua
l
pra
ct
ices
a
bo
ut
m
o
t
iv
a
t
io
n
lea
rning
T
h
e
r
esu
lts
p
o
in
ted
to
a
co
n
tr
ad
ictio
n
in
teac
h
er
s
’
p
er
ce
p
tio
n
s
of
s
tu
d
en
t
m
o
tiv
atio
n
.
W
h
ile
th
e
T
C
s
an
d
NPs
b
eliev
ed
p
u
p
ils
wer
e
more
d
r
iv
e
n
to
p
ass
th
e
ex
a
m
th
an
to
lear
n
th
e
lan
g
u
ag
e
,
th
e
AOs
d
is
ag
r
ee
d
.
T
h
e
AOs
also
u
n
d
er
lin
e
d
th
e
n
ec
ess
ity
f
o
r
p
u
p
ils
to
be
m
o
tiv
ated
to
lear
n
th
e
lan
g
u
a
g
e
an
d
th
at
lear
n
in
g
s
h
o
u
ld
be
en
j
o
y
ab
le,
as
d
o
cu
m
en
ted
by
E
r
d
o
ğ
an
[
4
9
]
a
n
d
B
o
r
g
[
4
5
]
.
T
h
ey
all
clar
if
ie
d
th
at
f
o
r
less
o
n
s
to
be
p
leasan
t,
s
tu
d
en
ts
m
u
s
t
ac
tiv
ely
p
ar
ticip
ate
in
th
e
class
r
o
o
m
.
On
th
e
o
th
er
h
an
d
,
d
ata
f
r
o
m
th
e
s
tim
u
lated
r
ec
all
in
ter
v
iews
co
n
d
u
cted
by
th
e
NPs
an
d
T
C
s
s
h
o
wed
t
h
at
r
ec
u
r
r
in
g
s
tu
d
e
n
ts
o
f
ten
l
ac
k
ed
m
o
tiv
ati
o
n
to
s
tu
d
y
an
d
wer
e
u
n
willin
g
to
p
ar
ticip
ate
in
class
ac
tiv
itie
s
.
T
h
ey
also
b
eliev
ed
th
at
s
o
m
e
p
u
p
ils
’
m
o
tiv
atio
n
f
o
r
lear
n
in
g
E
n
g
lis
h
m
ig
h
t
be
ex
a
m
-
f
o
cu
s
ed
.
T
h
is
r
esu
lt
alig
n
s
with
f
in
d
in
g
s
f
r
o
m
o
th
er
s
tu
d
i
es,
s
u
ch
as
th
o
s
e
by
th
e
ty
p
ical
au
t
h
o
r
s
[
3
8
]
,
[
4
5
]
.
T
C
s
an
d
NPs
f
r
eq
u
en
tly
b
elie
v
e
th
at
r
ewa
r
d
s
co
m
p
r
o
m
is
e
i
n
tr
in
s
ic
m
o
tiv
atio
n
,
as
was
co
v
er
ed
in
th
e
p
r
ev
i
o
u
s
s
ec
tio
n
[
5
0
]
.
In
ac
tu
ality
,
teac
h
er
s
claim
th
ey
ar
e
co
m
p
ell
in
g
.
W
h
en
ap
p
lied
ap
p
r
o
p
r
iately
,
r
ewa
r
d
s
m
ay
p
er
s
u
ad
e
lear
n
er
s
to
act
a
ce
r
tain
way
.
T
h
ey
m
ay
ev
e
n
h
elp
to
f
o
s
ter
a
f
ee
lin
g
of
co
m
m
u
n
ity
am
o
n
g
teac
h
er
s
an
d
p
u
p
ils
.
T
h
e
r
esu
lts
im
p
ly
th
a
t
one
T
C
,
f
o
r
in
s
tan
ce
,
th
o
u
g
h
t
u
tili
zin
g
ex
tr
in
s
ic
in
ce
n
tiv
es
was
h
elp
f
u
l
in
lear
n
er
au
to
n
o
m
y
an
d
m
o
tiv
atio
n
.
Sh
e
tu
r
n
e
d
th
is
n
o
tio
n
in
t
o
r
ea
lity
by
o
f
f
er
i
n
g
“g
if
ts
”
to
p
u
p
ils
in
th
e
class
r
o
o
m
a
n
y
tim
e
s
h
e
wis
h
ed
to
en
co
u
r
a
g
e
th
em
to
be
m
o
r
e
a
u
to
n
o
m
o
u
s
in
th
eir
lear
n
in
g
.
T
h
is
s
tr
ateg
y
ap
p
ea
r
s
to
be
ef
f
ec
tiv
e
s
in
ce
,
in
t
h
e
o
b
s
er
v
ed
class
r
o
o
m
,
p
u
p
ils
ar
e
en
g
ag
ed
an
d
r
ec
ep
tiv
e.
B
ec
au
s
e
th
ey
en
co
u
r
ag
e
b
e
h
av
io
r
al
co
m
p
lian
ce
,
th
ese
in
ce
n
tiv
es
f
r
eq
u
en
tly
p
r
o
v
id
e
r
esu
lts
im
m
ed
iately
[
5
1
]
.
Ho
wev
er
,
t
h
is
co
m
m
itm
en
t
lack
s
th
e
co
m
p
lete
en
g
ag
em
e
n
t
n
ec
ess
ar
y
f
o
r
o
p
tim
al
lear
n
in
g
an
d
well
-
b
ein
g
on
b
o
th
a
co
g
n
itiv
e
an
d
em
o
tio
n
al
lev
el
[
5
2
]
.
As
a
p
o
in
t
of
c
o
n
tr
o
l
in
th
e
cl
ass
r
o
o
m
,
th
e
NPs
an
d
T
C
s
also
u
s
ed
in
ce
n
tiv
es
a
n
d
a
c
o
n
ce
n
tr
atio
n
on
g
r
ad
es
an
d
s
co
r
es
in
ad
d
itio
n
to
ex
tr
i
n
s
ic
r
ewa
r
d
s
.
T
h
is
teac
h
in
g
a
p
p
r
o
a
ch
m
a
y
p
r
o
m
o
te
s
tu
d
en
t
lear
n
i
n
g
b
ec
au
s
e
ex
tr
in
s
ic
in
ce
n
tiv
es
ar
e
d
r
iv
en
by
ex
t
r
in
s
ic
co
n
tr
o
l.
T
h
u
s
,
teac
h
in
g
m
eth
o
d
s
wer
e
p
r
im
ar
ily
s
h
ap
e
d
by
th
e
teac
h
er
s
’
in
ten
tio
n
s
.
As
was
p
r
ev
io
u
s
ly
s
aid
,
m
an
y
teac
h
er
s
p
r
o
m
o
ted
th
e
n
o
tio
n
of
a
u
to
n
o
m
y
as
a
g
o
al,
b
eliev
in
g
th
at
if
th
ey
tau
g
h
t
th
eir
class
es
well,
th
eir
p
u
p
ils
m
ig
h
t
d
ev
elo
p
in
t
o
au
to
n
o
m
o
u
s
lear
n
er
s
wh
o
wer
e
r
ea
d
y
f
o
r
in
d
ep
en
d
en
t
s
tu
d
y
an
d
estab
lis
h
ed
f
o
r
life
.
A
more
p
r
ac
tical
ap
p
r
o
ac
h
to
m
o
tiv
atio
n
,
h
o
wev
er
,
co
u
ld
be
to
ad
o
p
t
a
co
n
ce
p
t
t
h
at
is
more
s
u
ited
to
th
e
AOs,
wh
er
e
s
elf
-
co
n
s
tr
u
ctio
n
an
d
ass
is
tan
ce
cr
ea
te
an
atm
o
s
p
h
er
e
m
o
tiv
atin
g
lear
n
i
n
g
.
In
co
n
clu
s
io
n
,
th
e
NPs
an
d
T
C
s
in
th
i
s
s
tu
d
y
th
o
u
g
h
t
p
u
p
ils
’
m
o
tiv
atio
n
to
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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2
2
5
2
-
8
8
2
2
I
n
t
J
E
v
al
&
R
es E
d
u
c
,
Vo
l
.
14
,
No
.
2
,
Ap
r
il
20
25
:
1
4
3
6
-
1
4
4
6
1442
lear
n
was
m
ain
ly
b
ased
on
g
r
ad
es
(
ex
ter
n
al
c
o
n
tr
o
l)
.
T
h
e
A
Os
n
o
n
eth
eless
s
tated
th
at
th
e
y
wan
t
th
eir
p
u
p
ils
to
be
o
r
g
an
ically
m
o
tiv
ated
.
4
.
1
.
3
.
T
hem
e
3:
t
e
a
cher
s
’
belief
s
a
nd
t
heir
a
ct
ua
l
pra
ct
ices
a
bo
ut
t
ea
cher
’
s
ro
les
Acc
o
r
d
in
g
to
th
is
s
tu
d
y
’
s
f
in
d
in
g
s
,
th
e
AOs
u
tili
ze
d
m
a
n
y
m
etap
h
o
r
s
to
d
escr
ib
e
th
eir
jo
b
s
as
ev
id
en
ce
th
at
teac
h
er
s
m
a
y
p
e
r
ce
iv
e
th
em
s
elv
es
as
tak
in
g
on
m
u
ltip
le
r
o
les
in
th
e
class
r
o
o
m
.
T
h
e
AOs’
u
s
ag
e
of
m
etap
h
o
r
s
lik
e
“
f
ac
ilit
ato
r
,
”
“g
u
id
e
,
”
“f
r
ie
n
d
,
”
“c
o
u
n
s
e
lo
r
,
”
an
d
“f
am
ily
m
em
b
e
r
”
s
u
g
g
ests
th
at
th
eir
r
esp
o
n
s
ib
ilit
y
was
to
in
s
tr
u
ct
an
d
ass
is
t
p
u
p
ils
in
th
eir
d
ay
-
to
-
d
a
y
liv
es.
In
co
n
tr
ast,
th
e
T
C
s
u
s
ed
th
e
m
etap
h
o
r
s
of
g
r
a
m
m
ar
an
aly
s
t
an
d
k
n
o
wled
g
e
tr
an
s
m
itter
s
to
ex
p
lain
th
eir
r
o
les.
T
h
e
g
r
a
m
m
ar
an
aly
s
t
an
d
m
etap
h
o
r
k
n
o
wled
g
e
tr
an
s
m
it
ter
s
u
g
g
ested
a
teac
h
er
wh
o
r
u
les
th
e
class
r
o
o
m
.
T
h
e
m
eta
p
h
o
r
s
“n
ar
r
ato
r
a
n
d
k
n
o
wled
g
e
p
r
o
v
id
e
r
”
wer
e
al
s
o
em
p
lo
y
ed
by
th
e
NPs
to
ch
ar
ac
ter
ize
th
eir
jo
b
,
wh
ic
h
wo
u
ld
o
n
ce
ag
ai
n
s
u
g
g
est
th
at
th
eir
p
r
im
a
r
y
d
u
t
ies
in
th
e
class
r
o
o
m
co
n
s
is
ted
of
p
r
o
v
id
i
n
g
p
u
p
ils
with
a
cr
u
cial
r
eso
u
r
ce
a
n
d
f
o
s
ter
in
g
th
eir
ac
ad
em
ic
d
ev
e
lo
p
m
en
t.
Play
in
g
a
s
u
p
p
o
r
tiv
e
r
o
le
p
r
esen
ted
s
o
m
e
ex
citin
g
id
ea
s
due
to
th
e
AOs’
co
n
v
er
s
atio
n
with
th
e
p
u
p
ils
.
T
h
e
AOs
also
allo
we
d
p
u
p
ils
to
s
p
ea
k
m
o
r
e
E
n
g
li
s
h
s
in
ce
th
ey
wer
e
co
n
s
id
er
ed
p
o
s
s
ess
o
r
s
of
f
r
esh
in
f
o
r
m
atio
n
g
ain
ed
v
ia
th
e
ir
s
tu
d
ies,
wh
ich
alig
n
s
with
th
e
n
o
tio
n
s
ab
o
u
t
ac
tiv
e
lear
n
in
g
m
en
tio
n
e
d
ea
r
lier
.
Mo
s
t
of
th
e
p
r
o
s
p
ec
tiv
e
T
u
r
k
is
h
teac
h
er
s
s
u
r
v
ey
ed
[
5
3
]
b
eliev
e
d
th
eir
f
u
n
ctio
n
as
k
n
o
wled
g
e
p
r
o
d
u
ce
r
s
q
u
alif
ied
th
e
m
to
teac
h
.
T
h
is
co
n
clu
s
io
n
co
n
f
licts
with
th
eir
f
in
d
in
g
s
.
T
h
er
ef
o
r
e,
p
u
p
ils
ar
e
p
ass
iv
e
r
ec
ip
ien
ts
of
k
n
o
wled
g
e.
D
esp
ite
th
e
NPs
’
claim
s
th
at
t
h
ey
h
ad
g
r
ad
u
ally
ad
o
p
ted
co
m
m
u
n
icativ
e,
s
tu
d
en
t
-
ce
n
ter
ed
teac
h
in
g
m
eth
o
d
s
in
s
tead
of
teac
h
e
r
-
d
o
m
in
an
t
,
g
r
am
m
a
r
-
o
r
ien
ted
o
n
es,
less
o
n
in
s
p
ec
tio
n
s
r
ev
ea
led
th
at
in
s
tr
u
ctio
n
was
u
n
q
u
e
s
tio
n
ab
ly
teac
h
er
-
d
o
m
in
a
n
t
an
d
in
ten
s
ely
f
o
cu
s
ed
on
g
r
am
m
ar
.
T
ea
ch
e
r
s
’
in
clin
atio
n
f
o
r
teac
h
er
-
d
o
m
in
an
t
a
p
p
r
o
ac
h
es
m
a
y
s
tem
f
r
o
m
th
eir
d
esire
to
m
ain
tain
p
ea
ce
an
d
o
r
d
e
r
.
T
h
e
T
C
s
d
escr
ib
ed
th
e
teac
h
er
’
s
f
u
n
ctio
n
as
one
of
th
e
s
o
u
r
ce
s
of
k
n
o
wl
ed
g
e.
Acc
o
r
d
in
g
to
th
is
v
iew
of
th
e
teac
h
er
’
s
d
u
ty
,
p
u
p
ils
wer
e
p
ass
iv
e
in
f
o
r
m
at
io
n
co
n
s
u
m
e
r
s
.
T
h
is
is
co
m
p
ar
ab
le
to
th
e
co
n
tr
o
l
-
f
o
cu
s
ed
in
d
iv
id
u
als
in
Ma
n
n
’
s
s
tu
d
y
,
wh
o
id
en
tifie
d
as
“m
an
ag
er
or
co
n
tr
o
ller
”
an
d
“p
o
licem
an
,
”
r
esp
ec
tiv
ely
,
an
d
w
h
o
e
x
p
r
es
s
ed
co
n
tr
o
l
as
a
wo
r
r
y
[
5
4
]
.
T
h
ese
r
esu
lts
ar
e
co
n
s
is
ten
t
with
Vietn
am
ese
s
o
ciety
,
wh
ich
h
o
l
d
s
teac
h
er
s
as
th
e
p
r
im
ar
y
a
n
d
f
in
al
ar
b
ite
r
s
of
th
eir
p
u
p
ils
’
ac
ad
em
ic
p
r
o
g
r
ess
.
4
.
1
.
4
.
T
hem
e
4:
t
e
a
cher
s
’
belief
s
a
nd
t
heir
a
ct
ua
l
pra
ct
ices
a
bo
ut
lea
rner
s
’
ro
les
T
h
e
m
o
s
t
h
i
g
h
ly
r
eg
ar
d
ed
as
p
ec
t
of
c
o
n
s
tr
u
ctiv
is
m
in
cla
s
s
r
o
o
m
s
was
th
e
r
o
les
of
th
e
lear
n
er
s
.
Acc
o
r
d
in
g
to
th
e
o
b
s
er
v
atio
n
d
ata
f
r
o
m
th
is
s
tu
d
y
,
wh
ile
th
e
AOs
an
d
NPs
h
eld
th
e
s
am
e
b
elief
th
at
s
tu
d
en
ts
s
h
o
u
ld
be
at
t
h
e
ce
n
ter
of
th
e
t
ea
ch
in
g
-
lear
n
in
g
p
r
o
ce
s
s
an
d
p
lay
a
v
ital
r
o
le
as
th
e
lea
d
in
g
ac
to
r
,
th
e
T
C
s
f
elt
th
at
lear
n
in
g
ap
p
ea
r
e
d
to
be
p
ass
iv
e,
wh
ile
th
e
teac
h
er
w
as
ac
tiv
e.
On
e
NP
h
eld
o
n
to
th
eir
v
iews
on
th
e
tr
ad
itio
n
al
teac
h
in
g
ap
p
r
o
ac
h
,
wh
ich
d
id
not
allo
w
s
tu
d
en
t
s
to
f
r
ee
ly
c
h
o
o
s
e
th
eir
lan
g
u
ag
e
u
s
e
or
s
u
g
g
est
co
u
r
s
e
co
n
ten
t
a
n
d
ac
tiv
ities
,
ev
en
if
t
h
ey
h
ad
a
p
o
s
itiv
e
v
iew
of
th
e
r
o
les
th
at
lear
n
er
s
s
h
o
u
ld
p
lay
.
T
h
e
teac
h
er
s
in
t
h
e
in
ter
v
iew
p
r
im
ar
ily
cr
e
d
ited
th
ei
r
s
tu
d
e
n
ts
’
in
ad
e
q
u
ate
E
n
g
lis
h
la
n
g
u
a
g
e
p
r
o
f
icien
cy
as
th
e
f
o
u
n
d
atio
n
f
o
r
th
eir
id
ea
s
.
T
h
e
r
esu
lts
ab
o
u
t
th
e
r
o
les
of
th
e
lear
n
er
s
do
n
o
t
s
ee
m
to
lin
e
up
with
th
o
s
e
of
o
th
er
ea
r
lier
r
esear
ch
[
5
5
]
,
[
5
6
]
wh
er
e
th
e
teac
h
er
s
th
o
u
g
h
t
f
av
o
r
ab
ly
of
t
h
e
CT
tech
n
iq
u
e
.
4
.
2
.
F
ind
ing
s
a
nd
dis
cu
s
s
io
n
s
f
o
r
re
s
ea
rc
h ques
t
io
n
2
T
h
e
d
ata
an
aly
s
is
h
ig
h
lig
h
ted
s
ev
er
al
f
in
d
in
g
s
in
an
s
wer
to
th
e
s
ec
o
n
d
s
tu
d
y
q
u
esti
o
n
ab
o
u
t
teac
h
er
s
’
p
er
s
p
ec
tiv
es
on
t
h
e
n
ee
d
f
o
r
ch
a
n
g
e.
First,
th
e
r
esu
lts
r
eg
ar
d
in
g
th
e
n
ec
ess
ity
an
d
co
n
f
o
r
m
ity
of
ch
an
g
e
as
p
er
ce
iv
ed
by
teac
h
er
s
s
h
o
wed
th
at
m
o
s
t
p
ar
ticip
an
ts
,
b
o
th
AOs
an
d
NPs
,
t
h
o
u
g
h
t
th
e
id
ea
of
ch
an
g
e
was
ap
p
r
o
p
r
iate
an
d
s
u
itab
le
in
g
en
er
al.
T
h
ese
r
esu
l
ts
d
em
o
n
s
tr
ated
th
at
AOs
an
d
ce
r
tain
NPs
alr
ea
d
y
know
th
e
ed
u
ca
tio
n
al
en
v
ir
o
n
m
en
t
m
u
s
t
im
p
r
o
v
e.
T
h
e
r
e
s
u
lts
also
d
em
o
n
s
tr
ate
th
e
r
elativ
ely
p
r
o
g
r
ess
iv
e
v
iews
of
th
e
AOs
an
d
s
o
m
e
N
Ps
in
th
i
s
s
tu
d
y
,
wh
o
b
eliev
e
th
at
a
lear
n
in
g
en
v
ir
o
n
m
en
t
s
h
o
u
ld
be
v
ib
r
a
n
t
an
d
d
y
n
am
ic,
in
ter
ested
in
o
n
g
o
i
n
g
p
r
o
f
ess
io
n
al
d
e
v
elo
p
m
e
n
t
,
an
d
awa
r
e
of
th
e
d
em
an
d
s
of
th
e
teac
h
in
g
p
r
o
f
ess
io
n
an
d
th
e
s
h
if
tin
g
g
lo
b
al
lan
d
s
ca
p
e.
T
h
is
ad
v
an
c
es
cu
r
r
icu
lar
r
ef
o
r
m
by
f
o
r
ci
n
g
ed
u
ca
t
o
r
s
to
be
d
y
n
am
ic
an
d
in
v
o
lv
e
d
in
th
eir
d
ev
elo
p
m
e
n
t.
I
n
ter
esti
n
g
ly
,
t
h
ese
r
esu
lts
co
n
tr
ad
ict
of
o
th
er
s
tu
d
ies
[
5
7
]
,
[
5
8
]
,
wh
o
f
o
u
n
d
th
at
teac
h
er
s
g
en
er
ally
n
eg
ativ
ely
p
er
ce
iv
ed
c
u
r
r
icu
lu
m
ch
a
n
g
e
a
n
d
r
ef
o
r
m
in
th
ei
r
s
tu
d
ies
in
s
ch
o
o
ls
in
th
e
Neth
er
lan
d
s
an
d
Ko
r
ea
b
ec
au
s
e
th
e
y
d
id
not
s
u
p
p
o
r
t
th
e
in
ten
d
e
d
CT
r
ef
o
r
m
.
Nev
er
th
eless
,
th
e
p
ar
ticip
an
ts
f
elt
th
at
th
e
n
ew
cu
r
r
icu
lu
m
was
u
n
wo
r
k
ab
le
an
d
im
p
r
ac
ti
ca
l
b
ec
au
s
e
p
ed
ag
o
g
ical
an
d
l
o
g
is
tical
co
n
s
id
er
atio
n
s
n
ee
d
ed
to
be
m
a
d
e
,
as
was
co
v
er
ed
in
t
h
e
s
ec
o
n
d
s
ec
tio
n
,
p
er
tin
e
n
t
to
teac
h
er
s
’
p
er
ce
p
ti
o
n
of
th
e
p
r
ac
ticality
of
ch
a
n
g
e.
T
h
is
h
ig
h
lig
h
ts
th
e
n
ec
ess
ity
of
tak
in
g
in
to
ac
co
u
n
t
th
e
ed
u
ca
tio
n
al
r
ea
liti
es
of
th
at
s
o
ciety
in
an
y
c
u
r
r
icu
l
u
m
r
ef
o
r
m
f
o
r
it
to
be
ef
f
ec
tiv
e.
T
h
ese
r
esu
lts
alig
n
with
o
th
er
r
esear
ch
[
5
9
]
,
w
h
o
d
is
c
o
v
er
ed
th
at
u
n
ju
s
tifie
d
ad
ju
s
t
m
en
ts
h
ad
a
d
etr
im
en
tal
im
p
a
ct
on
p
er
f
o
r
m
an
ce
in
h
is
in
v
esti
g
atio
n
of
th
e
L
ib
y
a
n
en
v
ir
o
n
m
en
t.
Acc
o
r
d
in
g
to
W
eb
er
[
6
0
]
in
a
n
aly
s
is
of
cu
r
r
icu
lar
d
ev
elo
p
m
en
t
in
So
u
th
Af
r
ica,
teac
h
er
s
m
u
s
t
be
d
ir
ec
tly
in
v
o
lv
e
d
in
id
ea
s
f
o
r
ch
an
g
e.
To
m
a
k
e
ch
an
g
e
a
r
ea
lity
,
th
ey
m
u
s
t
lear
n
to
tak
e
r
esp
o
n
s
ib
ilit
y
f
o
r
it,
ev
en
f
o
r
s
u
g
g
esti
o
n
s
m
a
d
e
by
th
e
s
tate
or
o
th
e
r
au
th
o
r
itativ
e
au
th
o
r
ities
.
Fu
r
th
er
m
o
r
e
,
in
in
v
esti
g
atin
g
cu
r
r
icu
lu
m
r
ef
o
r
m
in
d
ev
elo
p
in
g
co
u
n
tr
ies
,
s
u
ch
as
Vietn
am
,
s
tu
d
y
b
y
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t
J
E
v
al
&
R
es E
d
u
c
I
SS
N:
2252
-
8
8
2
2
A
q
u
a
lita
tive
ca
s
e
s
tu
d
y
o
f c
o
n
s
tr
u
ctivi
s
t te
a
ch
in
g
a
t a
h
ig
h
s
ch
o
o
l in
a
n
o
r
th
ern
…
(
P
h
a
m
Th
i Ki
eu
Oa
n
h
)
1443
Mo
n
ter
o
-
Sieb
u
r
th
[
6
1
]
f
o
u
n
d
th
at
“e
f
f
ec
tiv
e
an
d
in
n
o
v
ati
v
e
p
r
ac
tices
p
r
o
m
o
te
d
r
iv
e
c
h
an
g
e
an
d
m
an
ag
e
teac
h
er
-
led
cu
r
r
ic
u
lu
m
.
”
Sp
illan
e
et
a
l.
[
6
2
]
,
wh
o
r
e
v
iewe
d
s
tu
d
ies
on
im
p
lem
en
tin
g
e
d
u
ca
tio
n
al
p
o
licies,
teac
h
er
s
’
in
ab
ilit
y
to
p
ar
ticip
a
te
in
p
lan
n
in
g
m
ig
h
t
r
esu
lt
in
ac
cid
en
tal
p
er
f
o
r
m
an
ce
.
T
h
is
m
ig
h
t
be
b
ec
a
u
s
e
s
u
cc
ess
f
u
l
r
ef
o
r
m
im
p
lem
e
n
ta
tio
n
r
eq
u
i
r
es
more
e
x
ce
llen
t
in
f
o
r
m
atio
n
,
co
m
p
r
eh
en
s
io
n
,
an
d
ab
ilit
ies.
T
ea
ch
er
s
’
an
d
p
u
p
ils
’
r
ea
d
in
ess
f
o
r
th
e
ch
an
g
e
an
d
th
e
s
y
s
tem
’
s
r
ea
d
in
ess
f
o
r
ch
an
g
e
ar
e
also
co
v
er
ed
.
T
h
e
r
esear
c
h
f
in
d
in
g
s
s
u
p
p
o
r
t
th
e
n
o
tio
n
t
h
at
in
s
tr
u
cto
r
s
m
u
s
t
ac
q
u
ir
e
th
e
k
n
o
wled
g
e,
ab
ilit
ies,
an
d
s
k
ills
r
eq
u
ir
ed
to
im
p
lem
e
n
t
ch
an
g
e
in
th
e
class
r
o
o
m
s
u
cc
ess
f
u
lly
.
C
o
h
en
a
n
d
Hill
[
6
3
]
m
ad
e
a
s
im
ilar
o
b
s
er
v
atio
n
.
T
h
ey
claim
ed
t
h
at
it
is
u
n
r
ea
s
o
n
ab
le
to
e
x
p
ec
t
teac
h
er
s
to
ad
o
p
t
n
ew
p
ed
a
g
o
g
ical
ap
p
r
o
ac
h
es
with
o
u
t
s
u
f
f
icien
t
tr
ai
n
in
g
a
n
d
ed
u
ca
tio
n
on
th
e
s
ig
n
if
ican
ce
of
c
h
an
g
e.
Su
ch
a
d
ju
s
tm
en
ts
f
r
eq
u
e
n
tly
r
esu
lt
in
th
e
cu
r
r
icu
l
u
m
’
s
m
an
d
ate
not
b
ein
g
ap
p
lied
p
r
o
p
er
l
y
,
wh
ich
u
n
d
er
m
i
n
es
its
ef
f
ec
tiv
en
ess
.
4
.
3
.
F
ind
ing
s
a
nd
dis
cu
s
s
io
n
s
f
o
r
re
s
ea
rc
h ques
t
io
n
3
4
.
3
.
1
.
Do
ma
in
1:
t
e
a
cher
s
’
a
wa
re
nes
s
of
cha
nces
f
o
r
cha
ng
e
Acc
o
r
d
in
g
to
th
e
p
r
ev
io
u
s
s
tu
d
y
liter
atu
r
e
[
6
4
]
–
[
7
1
]
,
g
o
o
d
lead
er
s
h
ip
an
d
d
ir
ec
tio
n
ar
e
ess
en
tial
f
o
r
ed
u
ca
tio
n
al
r
ef
o
r
m
in
itiativ
es.
T
h
ese
f
ac
t
o
r
s
ar
e
also
v
e
r
y
e
f
f
ec
tiv
e
in
im
p
lem
en
tin
g
cu
r
r
ic
u
lar
m
o
d
if
icatio
n
s
.
T
h
ese
p
o
s
itio
n
s
-
s
u
ch
as
d
ep
a
r
tm
en
t
h
ea
d
s
or
d
ir
ec
to
r
s
-
ar
e
f
r
eq
u
en
tly
f
illed
by
s
ch
o
o
l
p
r
i
n
cip
als.
Fo
llo
win
g
Ha
et
a
l.
[
7
2
]
,
“
i
n
s
ch
o
o
ls
,
th
e
p
r
in
cip
al
h
as
a
u
n
i
q
u
e
p
o
s
itio
n
to
i
n
f
lu
en
ce
th
e
im
p
lem
en
tat
io
n
of
an
y
c
h
an
g
es
to
th
e
cu
r
r
icu
lu
m
an
d
th
e
im
p
ac
t
on
q
u
ality
.
”
T
h
e
r
ef
o
r
e
,
th
e
h
ea
d
ass
u
m
es
th
ese
d
ir
ec
tin
g
an
d
lead
in
g
r
esp
o
n
s
ib
ilit
ies
in
th
is
ca
p
ac
ity
.
T
h
e
c
u
r
r
en
t
s
tu
d
y
’
s
f
in
d
in
g
s
d
em
o
n
s
tr
ate
th
at,
to
e
f
f
ec
tiv
ely
ca
r
r
y
out
th
eir
lead
er
s
h
ip
d
u
ties
as
a
c
h
an
g
e
lead
er
,
th
e
p
r
in
cip
al,
d
ir
ec
to
r
,
or
d
ep
ar
tm
en
t
h
ea
d
m
u
s
t
p
a
y
clo
s
e
atten
tio
n
to
an
d
be
r
ec
ep
tiv
e
to
t
h
e
n
ee
d
s
of
th
e
g
e
n
er
al
p
u
b
lic.
4
.
3
.
2
.
Do
ma
in
2:
t
e
a
cher
s
’
t
ho
ug
hts
on
o
bs
t
a
cles
to
cha
ng
e
Similar
to
n
u
m
er
o
u
s
o
th
er
r
esear
ch
s
tu
d
ies
ex
a
m
in
in
g
th
e
li
m
itatio
n
s
of
CT
m
et
h
o
d
s
[
7
3
]
–
[
7
5
]
,
th
e
s
tu
d
y
’
s
f
in
d
in
g
s
d
em
o
n
s
tr
ate
d
th
at
test
s
y
s
tem
s
,
s
u
ch
as
th
e
u
n
iv
er
s
ity
ad
m
is
s
io
n
ex
a
m
an
d
th
e
g
en
er
al
ed
u
ca
tio
n
g
r
ad
u
atio
n
ex
am
,
h
a
d
s
ig
n
if
ican
tly
r
ed
u
ce
d
a
n
y
b
i
as
ag
ain
s
t
CT
p
er
f
o
r
m
an
ce
.
E
x
am
s
wer
e
f
o
u
n
d
to
be
b
o
th
a
f
ac
to
r
in
f
lu
e
n
cin
g
th
e
teac
h
in
g
s
tr
ateg
ies
u
s
ed
by
in
s
tr
u
cto
r
s
an
d
an
o
b
s
tacle
im
p
ed
in
g
th
eir
a
b
ilit
y
to
ap
p
l
y
th
e
cu
r
r
icu
lu
m
[
6
]
,
[
3
6
]
,
[
7
6
]
,
[
7
7
]
.
Gr
a
m
m
ar
is
th
e
m
ain
f
o
cu
s
of
ess
en
tial
test
s
in
Vietn
am
,
an
d
th
is
co
n
f
ir
m
s
th
e
r
esu
lts
of
m
u
ltip
le
p
r
io
r
r
esear
ch
[
7
8
]
,
[
7
9
]
,
wh
ich
s
h
o
wed
th
at
s
tu
d
en
ts
an
d
teac
h
er
s
wer
e
p
r
im
ar
ily
co
n
ce
r
n
e
d
with
ex
a
m
r
esu
lts
,
p
lacin
g
tr
em
e
n
d
o
u
s
p
r
ess
u
r
e
on
t
h
em
an
d
im
p
ac
ti
n
g
th
eir
in
s
tr
u
ctio
n
.
Seco
n
d
ly
,
b
ec
a
u
s
e
th
e
tr
ain
in
g
s
ess
io
n
s
o
f
f
er
ed
to
ass
is
t
p
ar
ticip
an
ts
in
th
e
cu
r
r
en
t
s
tu
d
y
wer
e
n
eith
er
r
eg
u
lar
nor
p
r
ac
ticab
le,
th
e
p
a
r
ticip
an
ts
v
o
iced
d
is
p
leasu
r
e
with
th
e
m
.
T
h
is
h
ig
h
lig
h
ts
th
e
im
p
o
r
t
an
ce
,
n
ec
ess
ity
,
an
d
r
elev
an
ce
of
teac
h
er
p
r
e
p
ar
ati
o
n
p
r
o
g
r
am
s
.
T
h
e
im
p
o
r
tan
ce
of
f
ir
s
t
tr
ain
i
n
g
’
s
q
u
ality
an
d
r
elev
an
ce
was
also
u
n
d
er
lin
e
d
by
s
ev
er
al
r
esear
c
h
er
s
[
6
2
]
,
[
6
7
]
,
so
th
at
it
wo
u
ld
b
e
co
m
e
a
teac
h
er
’
s
d
ef
a
u
lt
s
k
ill
s
et.
W
h
ile
Vietn
am
’
s
ed
u
ca
tio
n
p
o
licies
h
av
e
lo
n
g
h
ig
h
lig
h
ted
th
e
i
m
p
o
r
tan
ce
of
p
r
o
d
u
ci
n
g
h
ig
h
-
q
u
ality
teac
h
er
s
,
in
ac
tu
ality
,
teac
h
er
tr
ain
in
g
p
r
o
g
r
am
s
h
av
e
not
b
ee
n
v
er
y
s
u
cc
ess
f
u
l
in
f
u
lf
illi
n
g
th
e
n
ee
d
s
of
teac
h
er
s
.
T
h
e
o
p
in
io
n
s
of
h
ig
h
s
ch
o
o
l
teac
h
er
s
ab
o
u
t
th
eir
d
em
a
n
d
s
f
o
r
p
r
o
f
ess
io
n
al
d
ev
el
o
p
m
en
t
ar
e,
in
f
ac
t,
not
well
-
s
tu
d
ied
.
T
h
e
r
esear
ch
c
o
n
f
ir
m
s
th
e
n
ec
ess
ity
f
o
r
teac
h
er
p
r
ep
ar
atio
n
p
r
o
g
r
a
m
s
th
at
ad
ap
t
to
th
e
co
n
s
tan
tl
y
ev
o
lv
in
g
n
ee
d
s
of
th
e
m
o
d
er
n
wo
r
ld
,
p
ar
tic
u
lar
ly
th
e
lac
k
of
n
ew
cu
r
r
icu
la.
4
.
3
.
3
.
Do
ma
in
3:
t
e
a
cher
s
’
perc
ept
io
ns
of
nece
s
s
a
ry
co
nd
it
io
ns
to
s
up
po
rt
CT
pra
ct
ic
es
T
h
e
p
ar
ticip
an
ts
’
co
m
m
e
n
ts
in
d
icate
th
at
in
s
titu
tio
n
al
s
u
p
p
o
r
t
is
n
ec
ess
ar
y
f
o
r
a
m
u
ltifa
ce
ted
an
d
ch
allen
g
in
g
p
r
o
ce
s
s
lik
e
cu
r
r
i
cu
lar
r
ev
is
io
n
.
Fin
an
cial
r
eso
u
r
ce
s
m
u
s
t
be
s
p
en
t
on
teac
h
er
d
ev
elo
p
m
e
n
t,
to
o
ls
,
an
d
class
r
o
o
m
s
etu
p
to
p
r
o
v
i
d
e
th
is
s
u
p
p
o
r
t.
T
h
e
p
ar
ticip
an
t
s
’
r
ep
lies
r
ev
ea
led
t
h
eir
ad
m
i
r
atio
n
an
d
h
ap
p
in
ess
with
th
e
o
r
g
a
n
izatio
n
’
s
wo
r
k
an
d
th
e
f
in
an
cial
ass
is
tan
ce
g
iv
en
.
It
s
h
o
u
ld
be
em
p
h
asized
th
at
m
an
y
Vietn
am
ese
ed
u
ca
tio
n
al
in
s
titu
tio
n
s
do
not
ty
p
ically
o
p
er
ate
in
th
is
m
an
n
er
.
5.
CO
NCLU
SI
O
N
T
h
e
p
r
esen
t
in
v
esti
g
atio
n
h
as
s
u
b
s
tan
tially
co
n
tr
ib
u
te
d
to
th
e
p
er
tin
en
t
t
h
eo
r
y
,
m
eth
o
d
o
lo
g
y
,
an
d
p
r
ac
tice
liter
atu
r
e.
In
ter
m
s
of
th
eo
r
etica
l
co
n
tr
ib
u
tio
n
s
,
th
e
cu
r
r
en
t
s
tu
d
y
is
th
e
f
ir
s
t
of
its
k
in
d
in
Vietn
am
to
ex
am
in
e
CT
m
eth
o
d
s
an
d
b
elief
s
am
o
n
g
h
ig
h
s
ch
o
o
l
te
ac
h
er
s
f
r
o
m
th
r
ee
d
if
f
e
r
en
t
p
ar
ticip
an
t
g
r
o
u
p
s
,
s
p
ec
if
ically
th
e
AOs,
NPs
,
an
d
T
C
s
,
an
d
th
eir
v
iews
on
th
e
p
r
er
eq
u
is
ites
f
o
r
im
p
r
o
v
ed
CT
m
eth
o
d
s
an
d
th
eir
wo
r
r
ies
ab
o
u
t
th
e
n
ec
ess
ity
f
o
r
ch
an
g
e.
Acc
o
r
d
i
n
g
ly
,
t
h
e
f
in
d
in
g
s
f
r
o
m
th
e
s
tu
d
y
i
d
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CT
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eth
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s
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wh
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al
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h
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s
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o
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th
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s
tu
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ay
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av
e
co
n
t
r
ib
u
ted
to
ch
a
n
g
in
g
th
eir
m
eth
o
d
s
.
T
h
is
s
tu
d
y
aim
s
to
co
m
p
r
eh
en
d
CT
im
p
l
em
en
tatio
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th
r
o
u
g
h
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ig
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ch
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teac
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s
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p
in
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s
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d
e
x
p
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ien
ce
s
.
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h
u
s
,
t
h
e
s
tu
d
y
f
o
cu
s
ed
on
a
s
p
ec
if
ic
co
m
p
o
n
en
t
of
teac
h
er
s
’
CT
id
ea
s
an
d
how
th
o
s
e
v
iew
s
wer
e
m
ir
r
o
r
ed
in
teac
h
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s
’
in
s
tr
u
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n
al
s
tr
ateg
ies.
T
h
er
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o
r
e,
th
e
r
esear
ch
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s
s
u
g
g
est
th
e
f
o
llo
win
g
to
u
n
d
e
r
s
tan
d
f
u
r
th
er
how
CT
is
u
s
ed
in
Vietn
am
.
In
lig
h
t
of
th
is
,
it
is
also
ad
v
is
ed
to
u
n
d
er
tak
e
em
p
ir
ical
r
esear
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th
at
will
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m
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to
f
in
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in
g
s
b
a
s
ed
on
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a
n
d
m
ea
s
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p
h
en
o
m
en
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an
d
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f
f
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n
u
m
er
ical
d
ata
t
h
at
is
ea
s
ily
g
en
er
aliza
b
le
ac
r
o
s
s
ca
s
e
s
tu
d
ies
an
d
s
tu
d
y
s
ites
.
RE
F
E
R
E
NC
E
S
[
1
]
S
.
M
.
W
i
l
s
o
n
,
R
.
E.
F
l
o
d
e
n
,
a
n
d
J.
F
e
r
r
i
n
i
-
M
u
n
d
y
,
“
Te
a
c
h
e
r
p
r
e
p
a
r
a
t
i
o
n
r
e
sea
r
c
h
:
a
n
i
n
s
i
d
e
r
’
s
v
i
e
w
f
r
o
m
t
h
e
o
u
t
si
d
e
,
”
J
o
u
rn
a
l
o
f
T
e
a
c
h
e
r E
d
u
c
a
t
i
o
n
,
v
o
l
.
5
3
,
n
o
.
3
,
p
p
.
1
9
0
–
2
0
4
,
M
a
y
2
0
0
2
,
d
o
i
:
1
0
.
1
1
7
7
/
0
0
2
2
4
8
7
1
0
2
0
5
3
0
0
3
0
0
2
.
[
2
]
N
.
W
.
N
a
m
u
n
g
a
a
n
d
R
.
N
.
O
t
u
n
g
a
,
“
Te
a
c
h
e
r
e
d
u
c
a
t
i
o
n
a
s
a
d
r
i
v
e
r
f
o
r
s
u
st
a
i
n
a
b
l
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l
o
p
m
e
n
t
i
n
K
e
n
y
a
,
”
I
n
t
e
r
n
a
t
i
o
n
a
l
J
o
u
r
n
a
l
o
f
H
u
m
a
n
i
t
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e
s
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d
S
o
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i
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e
,
v
o
l
.
2
,
n
o
.
5
,
p
p
.
2
2
8
–
2
3
4
,
2
0
1
2
.
[
3
]
La
w
o
n
Ed
u
c
a
t
i
o
n
V
i
e
t
n
a
m
.
“
L
a
w
N
o
.
4
3
/
2
0
1
9
/
Q
H
1
4
,
A
r
t
i
c
l
e
6
6
.”
[
4
]
M
.
B
.
C
a
r
l
i
n
,
“
I
mp
r
o
v
i
n
g
h
i
g
h
sc
h
o
o
l
s
t
u
d
e
n
t
s’
p
e
r
f
o
r
m
a
n
c
e
v
i
a
d
i
sc
o
v
e
r
y
l
e
a
r
n
i
n
g
,
c
o
l
l
a
b
o
r
a
t
i
o
n
a
n
d
t
e
c
h
n
o
l
o
g
y
,
”
T
.
H
.
E
.
J
o
u
rn
a
l
,
v
o
l
.
2
4
,
n
o
.
1
0
,
p
p
.
6
2
–
6
5
,
1
9
9
7
.
[
5
]
D
.
G
.
D
e
e
d
s
a
n
d
C
.
S
.
A
l
l
e
n
,
“
A
n
e
w
p
a
r
a
d
i
g
m
i
n
i
n
t
e
g
r
a
t
e
d
mat
h
a
n
d
s
c
i
e
n
c
e
c
o
u
r
se
s,”
J
o
u
rn
a
l
o
f
C
o
l
l
e
g
e
S
c
i
e
n
c
e
T
e
a
c
h
i
n
g
,
v
o
l
.
3
0
,
n
o
.
3
,
p
p
.
1
7
8
–
1
8
4
,
2
0
0
0
.
[
6
]
M
.
G
o
r
d
o
n
,
“
Th
e
m
i
su
ses
a
n
d
e
f
f
e
c
t
i
v
e
u
s
e
s
o
f
c
o
n
s
t
r
u
c
t
i
v
i
st
t
e
a
c
h
i
n
g
,
”
T
e
a
c
h
e
rs
a
n
d
T
e
a
c
h
i
n
g
:
T
h
e
o
ry
a
n
d
P
ra
c
t
i
c
e
,
v
o
l
.
1
5
,
n
o
.
6
,
p
p
.
7
3
7
–
7
4
6
,
N
o
v
.
2
0
0
9
,
d
o
i
:
1
0
.
1
0
8
0
/
1
3
5
4
0
6
0
0
9
0
3
3
5
7
0
5
8
.
[
7
]
C
.
T
.
F
o
s
n
o
t
,
C
o
n
s
t
r
u
c
t
i
v
i
s
m
,
t
h
e
o
r
y
,
p
e
r
s
p
e
c
t
i
v
e
s
,
a
n
d
p
r
a
c
t
i
c
e
.
N
e
w
Y
o
r
k
:
T
e
a
c
h
e
r
s
C
o
l
l
e
g
e
P
r
e
s
s
,
1
9
9
6
.
[
8
]
C
.
W
i
t
f
e
l
t
,
“
Ed
u
c
a
t
i
o
n
a
l
m
u
l
t
i
m
e
d
i
a
a
n
d
t
e
a
c
h
e
r
s’
n
e
e
d
s
f
o
r
n
e
w
c
o
mp
e
t
e
n
c
i
e
s
:
a
st
u
d
y
o
f
c
o
m
p
u
l
s
o
r
y
sc
h
o
o
l
t
e
a
c
h
e
r
s’
n
e
e
d
s
f
o
r
c
o
m
p
e
t
e
n
c
e
t
o
u
se
e
d
u
c
a
t
i
o
n
a
l
m
u
l
t
i
me
d
i
a
,
”
Ed
u
c
a
t
i
o
n
a
l
M
e
d
i
a
I
n
t
e
r
n
a
t
i
o
n
a
l
,
v
o
l
.
3
7
,
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o
.
4
,
p
p
.
2
3
5
–
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4
1
,
Ja
n
.
2
0
0
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,
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1
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0
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5
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2
0
.
[
9
]
P
.
N
g
u
y
e
n
,
C
.
T
e
r
l
o
u
w
,
a
n
d
A
.
P
i
l
o
t
,
“
C
u
l
t
u
r
a
l
l
y
a
p
p
r
o
p
r
i
a
t
e
p
e
d
a
g
o
g
y
:
t
h
e
c
a
se
o
f
g
r
o
u
p
l
e
a
r
n
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n
g
i
n
a
C
o
n
f
u
c
i
a
n
H
e
r
i
t
a
g
e
C
u
l
t
u
r
e
c
o
n
t
e
x
t
,
”
I
n
t
e
rc
u
l
t
u
r
a
l
E
d
u
c
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t
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o
n
,
v
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l
.
1
7
,
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o
.
1
,
p
p
.
1
–
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9
,
M
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r
.
2
0
0
6
,
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:
1
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1
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4
6
7
5
9
8
0
5
0
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5
0
2
1
7
2
.
[
1
0
]
P
.
T
.
H
.
T
h
a
n
h
,
“
I
s
s
u
e
s
t
o
c
o
n
s
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d
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w
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n
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A
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d
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c
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t
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n
s
t
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t
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t
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o
n
s
,
”
J
o
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a
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H
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h
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r
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d
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c
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t
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P
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.
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3
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o
.
5
,
p
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[
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8
]
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[
5
0
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[
5
1
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.
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[
5
2
]
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R
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E.
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[
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[
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4
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.
[
5
5
]
C
.
P
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[
5
6
]
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.
A
.
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5
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[
5
7
]
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M
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:
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[
5
8
]
I
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C
.
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4
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.
[
5
9
]
S
.
M
.
O
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,
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s,”
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.
[
6
0
]
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.
W
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r
,
“
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n
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a
n
d
b
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k
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f
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Art
s i
n
Q
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R
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:
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c
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Me
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C
A
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