Question

【题目】–Must we clean the classroom at once?–No, you _______. You _______ clean it after school.
A.mustn't; may
B.may not; must
C.don't have to; may
D.can't; must

Answer 1

【答案】C
【解析】句意：---我们必须马上打扫教室吗？---不，你不必，你可以放学后打扫。回答must的问句，肯定用must，必须；否定用needn't或者don't have to，不必。may可以。根据句意，所以答案是C。