问题

May I smoke here? —If you _____, choose a seat in the smoking section.
A:should
B:could
C:may
D:must
B:could
C:may
D:must
正确答案是:
同类题型
He _______ more visits to his parents.He has been regretting not doing so since they passed away.
108. We spoke in whispers ______ waking thebaby.
Look! Two ______ are playing basketball onthe playground(操场).
There was a (an) __________ silence betweenus after we were left alone in the sitting-room.