We teachers should ______ students ______ us questions in class. 
#48995
A
be allowed, to ask
B
let, to ask
C
encourage, to ask
D
allow, ask
推荐题目
Every day I spend two hours ______ my homework.
#49479
A
finishingtodo
B
finishingdoing
C
tofinishtodo
D
tofinishdoing
Jane likes singing.We often hear her ______ after class. 
#49746
A
sing
B
to sing
C
sings
D
singing
They promised        your minds        , or you will get your money back.
#50255
A
change; successful
B
to change; successful
C
change; successfully
D
to change; successfully
I try ___ a lot of vegetables.
#50912
A
to eat
B
eating
C
eat
D
to have eating