Question

Colin was about to get off the camel ________ a child ran towards him.

1. A.
   while
2. B.
   when
3. C.
   as
4. D.
   since

Answer 1

B
试题分析：考查固定结构：be about to do when…刚要做…这时…，句意：Colin刚要下骆驼这时一个男孩朝他跑过来。选B。
考点：考查固定结构
点评：和when常常搭配的固定用法还有：过去完成时（had done）…when…,过去进行时（was/were doing +when…）。