— May we leave the classroom now?— No you . You to leave until the bell rings.A. mustn’t

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. can’t; aren’t allowed

C. don’t have to; are allowed

D. needn’t; aren’t allowed

答案：

A. mustn’t; are allowed

(答案→)B. can’t; aren’t allowed

C. don’t have to; are allowed

D. needn’t; aren’t allowed

解析：may的否定回答应该用can’t，表示不能，不可以；而mustn’t表示禁止，一般不做否定回答；don’t have to表示不必；needn’t是must的否定回答，表示“不必”。所以本题选B。