I am a League member. I volunteer my time ___________ others. 
#48828
A
help
B
to help
C
helping
D
helped
推荐题目
Drivers are warned___________when they are tired.
#50433
A
to drive
B
not drive
C
not to drive
D
not driving
It’s time        .
#50478
A
for breakfast
B
have breakfast
C
for I to have breakfast
D
for have breakfast
I spent half an hour ___________ my homework. 
#49163
A
finish doing
B
to finish doing
C
finishing to do
D
finishing doing