Yesterday morning I was just leaving---the telephone ran Wap版

试题详情及答案解析

Yesterday morning I was just leaving---the telephone rang.

A．when

B．while

C．because

D．since

答案：A

试题分析：句意：昨天早上我正要离开时电话铃响了。When当……时；while当……时； because 因为；since自从。表示某事正在进行时发生了另一件事，常用when，所以选A。
考点：考查连词的用法