问题

_____ does your mother usually go to the office—By bus.
A:can
B:may
C:need
D:must;
B:may
C:need
D:must;
正确答案是:
同类题型
It is difficult for us to learn a lesson in life______ we’ve actually had that lesson
It is reported that _______ people in the world are suffering from the H1N1 flu.
Don’t smoke here, Dad. Smoking _____ in public places.–Oh, sorry. I’ll stop right now.
So often ______ inrecent years that it has almost become a rule