例句：

　　1、Benjamin was forced to admit what he had been doing．

　　本杰明被迫承認(rèn)他所做的一切。

　　2、I had told people what he had been doing, so now the police were onto him.

　　我已將他的所作所為告訴了別人，因此現(xiàn)在警方正在追查他。

　　3、Until this summer, China had been doing that carefully.

　　截止今年夏天，中國(guó)一直在審慎地這么做。

　　4、I had been doing the work for two hours when the teacher came.

　　老師來(lái)時(shí)那件工作我已做了兩小時(shí)了。&當(dāng)時(shí)工作尚未完成，所以老師來(lái)了我還繼續(xù)在做。

　　5、Everybody knew what he had been doing all those years.

　　大家都知道那些年他在做什么。