---Will you be back five in the afternoon?　---I’m not sure maybe later than that. A. in　

问题补充：

---Will you be back five in the afternoon?

---I’m not sure, maybe later than that.

A. in

B. before

C. for

D. until

答案：

A. in

(答案→)B. before

C. for

D. until

解析：考察介词用法，四个选项发表表示在……里面、在……之前、为了……和直到……。根据答语，我不确定。可能比那个时候晚。可知问句时间应该是在某个时间点之前。Until表示持续性的时间，不可和be back连用，故选B，你会在下午五点前回来吗？