问题补充:
---Must I clean the floor now?
---. It is too dirty.
A. Yes, you needn’t
B. No, you needn’t
C. No, you mustn’t
D. Yes, you must
答案:
A. Yes, you needn’t
B. No, you needn’t
C. No, you mustn’t
(答案→)D. Yes, you must
解析:对于must 引导一般疑问句的肯定回答为yes ,….must否定回答为no,….needn’t/don’t have to,故选D