问题补充：
Can you buy me a birthday cake the afternoon?
Sorry, I busy. I can do it Sunday afternoon.
A. on, in
B. in, on
C. in, at
D. on, at
答案：
A. on, in
(答案→)B. in, on
C. in, at
D. on, at
解析：句意：上句下午你能给我买个生日蛋糕吗？下句回答对不起，我很忙但是在星期天上午我可以买，inthe afternoon在下午，on 加具体的某天上下午，onSundayafternoon在星期天下午根据句意故选B。
