Mum,may i go out to play ? -No,you ( ) .you must finish your homework first如何回答A.may not B.mustn't C.couldn't D.needn't参考答案选B，我觉得有问题
问题描述：
Mum,may i go out to play ? -No,you ( ) .you must finish your homework first如何回答
A.may not B.mustn't C.couldn't D.needn't
参考答案选B，我觉得有问题
答
看意思BC都可以，B强硬，C委婉，因为是妈妈和孩子说话，所以强硬，参考答案该是这个解释
答
B
答
B mustn't 禁止，不许
答案没有问题。
答
B或can't
couldn't 不对，时态不对，
对must回答一般用can或cannot，用must也行
答
No, you mustn't 选 B . may的否定回答用mustn't 和can't. 这里couldn't是过去时