问一个英语问题...

来源：百度知道 编辑：UC知道 时间：2024/05/31 19:23:32
Tom didn't sleep ( ) his mother came back.

A. when
B. while

选什么

选A
如果用while不管什么情况 从句种必须用进行时态。

A
his mother came back，came back是一瞬间的，不能用while

A,while要同时都进行时

A
This page contains information about how to answer the question and prepare food while doing outdoor activities.
while前面不一定要用进行时，而后面一定要用进行时~
不过现在不要太在意语法,目的是说好英语.