-- How long do you think it will be the bus arrives here?-- No more than five minutes.A.

问题补充：

-- How long do you think it will be the bus arrives here?

-- No more than five minutes.

A. when

B. before

C. since

D. after

答案：

A. when

(答案→)B. before

C. since

D. after

解析：考查句型：It will + 一段时间+ before…，要多长时间才…,句意：你认为还要多久公共汽车才能到？--不到5分钟。选B。