If you sit in a chair _____a long time, your back may begin to hurt.
#50771
A
at
B
in
C
on
D
for
推荐题目
---Vegetables are good _______our health.---Yes. I agree _______ you. 
#49638
A
for; with
B
at; with
C
for; to
D
at; to
He ____ his homework ____ Sunday.
#47859
A
doesn’t , on
B
don’t do, in
C
doesn’t do, on
D
don’t do, on
Let’s ______ each other.
#48848
A
to make friends
B
make friends to
C
make friends with
D
to make friends with