问题补充:
May we leave the classroom now? No, you . You to leave until the bell rings.
A. mustn’t, are allowed
B. don’t have to , are supposed
C. needn’t , aren’t allowed
D. can’t , aren’t supposed
答案:
A. mustn’t, are allowed
B. don’t have to , are supposed
C. needn’t , aren’t allowed
(答案→)D. can’t , aren’t supposed
解析:否定回答可用can ,mustn 或may not,may not 可能不,can 不能够,mustn 一定不,禁止;be allowed to被允许做某事;be supposed to应该,被期望做某事;句意:我们现在可以离开教室吗?不,你们不能。你们直到铃响才能离开教室。结合语境可知前文用can’t,mustn’t语气较重,may not语气太轻。同理,be allowed to语气则太重,故选D,为最佳答案。