I come back before 6 o’clock?---No you But you be back later than 7 o’clock．A. Need

问题补充：

--- I come back before 6 o’clock?

---No，you ．But you be back later than 7 o’clock．

A. Need；must；must

B. May；mustn’t；can’t

C. Can；can’t：can’t

D. Must；needn’t；can’t

答案：

A. Need；must；must

B. May；mustn’t；can’t

C. Can；can’t：can’t

(答案→)D. Must；needn’t；can’t

解析：根据情态动词的问与答，符合题意的只有D