There must be many people ________ for their trains at the train station because of the golden week holiday.
#49141
A
are waiting
B
waited
C
to wait
D
waiting
推荐题目
---How did you work out the difficult chemistry problem?--- I worked it out by ________.
#49667
A
working with a group
B
think very hard
C
ask the teacher for help
D
doing oneself
—Before he went abroad, he spent as much time as he ____ English. 
#50421
A
could learning
B
learned
C
to learn
D
could learn