Mum could I play with my classmates for a while after I finish my homework?- . But

问题补充：

--- Mum, could I play with my classmates for a while after I finish my homework?

--- . But you must come back before supper.

A. Yes, you can

B. Yes, you could

C. No, you can’t

D. No, you couldn’t

答案：

(答案→)A. Yes, you can

B. Yes, you could

C. No, you can’t

D. No, you couldn’t

解析：本题答语的含义是晚饭前你必须回家，根据答句的含义应该是对问句的肯定，could构成的的一般疑问句，回答是不在拥有委婉礼貌的语气，不在用could，而应该用can，故本题选A。