—Was it under the tree you went away talking to a friend?
—Sure. But when I got back there, the bike was gone.
A. that
B. when
C. where
D. while
网友回答
A. that
(答案→)B. when
C. where
D. while
解析：考查时间状语从句：做好此题的关键是正确理解上下文的语境。在此句中，it是代词，指代 the bike，句意为：“当你离开去同朋友谈话的时候，你的自行车是在这树下吗?”“当然，但当我回来时，自行车就不见了。”假若 A，为强调句，句子即为 Was it under the tree that you were away talking to a friend? 把强调部分去掉：句子则为 Under the tree while you were talking to a friend，不成立一个句子。选 B。