-- we clean the classroom at once?
--No, you . You clean it after school.
A. Must, needn’t, may
B. Must, mustn’t, can
C. Shall, can’t, must
D. Need, mustn’t, may
网友回答
(答案→)A. Must, needn’t, may
B. Must, mustn’t, can
C. Shall, can’t, must
D. Need, mustn’t, may
解析：考查情态动词.must必须,否定回答一般借助于needn’t或者don’t have to.shall一般用将来时态,need需要.句意:我们必须现在就打扫教室吗？不，你们不必。你们可以放学后在打扫。故选A。