had been done 表示过去的过去,是过去完成的被动态时。(当你想说发生在过去的两件事时,就要分清谁先谁后。先发生的用过去完成时,后发生的要用过去时)。

如:

The rooms had been cleaned when I came.

我来的时候,房间已经被打扫了。

扩展资料

By the end of last month, all the work had been done.

到上个月末为止，所有的工作都完成了。

Nothing like this had been done before.

之前没人这么做过。

Chromosome test had been done in eight patients.

染色体检查8例均正常。

It is as though no preparatory work had been done.

就好像与会者没有做任何准备工作。

The work had not been done very thoroughly.

这工作做得不太认真。