用括号中的时间状语改写句子

The children were playing chess at 4:00 pm yesterday.
What were you doing at that time?
I was listening to the radio when Mother came back.

1楼的对的,我估计你们现在在学过去进行时吧

一、 概念和用法：过去进行时表示在过去某一时刻或某一段时间内进行或发生的动作。其形式为was /were + V-ing。常与表示过去的时间状语连用，如：last night, last Saturday等；或者与when, while, as引导的过去时间状语连用。例如：
We were watching TV from seven to nine last night. 昨天晚上七点到九点的时候我们在看电视。
What was he researching all day last Sunday? 上周日他一整天都在研究什么？
二、 过去进行时可以表示在过去某个时间点发生的事情。时间点可以用介词短语、副词或从句来表示。如：
What was she doing at nine o‘clock yesterday? 昨天晚上九点她在做什么？ (介词短语表示时间点)
When I saw him he was decorating his room. 当我看见他的时候他正在装饰房间。 (when从句表示时间点)
三、 在复合句中，如果主要动作和背景动作都是延续的或同时发生的，那么主从句的动词都可用过去进行时。例如：
While he was waiting for the bus, he was reading a newspaper.他边等车边看报。 (两个动作都是延续的)
He was cleaning his car while I was cooking. 他擦车时我在做饭。(两个动作同时进行)
四、 通常不能用于过去进行时的动词主要有：agree, be, believe, belong, care, forget, hate, have(拥有), hear,