was been doing是什么時態(tài)

　　例句：

　　1、I was wondering if you were doing anything this weekend.

　　我想知道這個周末你是否要做什么。

　　2、While they were doing their homework, I was doing the laundry.

　　他們在做家庭作業(yè)的時候，我正在洗衣服。

　　3、It was the locals who felt like what they were doing was dangerous.

　　當?shù)厝擞X得，他們這么做是很危險的。

　　4、He was doing this for himself, not for his father.

　　他這么做是為了自己，不是為父親。

　　5、He knew exactly what he was doing.

　　他清楚地知道自己在做什么。