wasreading是什么时态

　　例句：

　　This time yesterday Jack was not watching TV. He was repairing his bike.

　　昨天这个时候，杰克不是在看电视，而是在修理自行车。

　　We were having supper when the phone rang.

　　我们正在吃晚饭时电话响了。

　　Were you playing basketball at four yesterday afternoon?

　　昨天下午四点你们在打篮球吗？

　　While we were talking, the teacher came in.

　　当我们正在谈话时,老师进来了。