现在完成时的被动态

（1）肯定式句型：have/ has +been +done

例句：
1.Many studies have been done over the years on various aspects of Web and interface design, and the findings are valuable in helping us improve our work.
这些年，很多人在网站和界面设计的很多方面完成了很多的研究，这些结论在帮助我们提高我们的工作方面很有价值。

2.But even though green tea gets a lot of props for its reputation as a healing brew, most of the studies on its effects have been done in the laboratory or in animals.
虽然绿茶有很多好处使它享有保健品的美誉，但是，对于它的影响的实验仍然在实验室或者动物身上大量进行着。

3.But by that point, the damage will have been done.
但是这么看来，带来的破坏似乎已经到头了。

（2）否定式为：have/ has +not +been +done

例句：
1.Her story has not been published.
她的故事还没有被出版。

2.His homework has not been done.
他的作业还没写完。

3.Mike has not been seen for a long time.
麦克已经很久没被看到了。 

（3）一般疑问句需将have /has提到主语的前面。

例句：
1.Has her story been read?
她的故事被看过了吗？

2.Have your pen been found?
你的笔被找到了吗？

3.Has the seat been ordered?
这个位置被预定了吗？

（4）特殊疑问句为：疑问词+have /has +been +done?

例句：
1.Who has been investigated?
谁被调查了？

2.Where has the book been taken?
这书被带到哪儿了？

3.When has the house been built?
这所房子什么时候建的？