关于什么是独立主格结构和非谓语动词的区别!区别和用法都说下
1个回答

Having been done 是现在分词的完成时的被动语态,用的时候常常会出现一个段时间状语.如:

Having been built for two years, the building will be used as a hospital

done是过去分词,表示被动和完成,如

completed last month, the building will be used as a hospital

having done 是现在分词的完成时的主动形式,用的时候常常会出现一个段时间状语.如

Having worked for a long time , the workers are all very tired.

这些看完了你应该知道题目怎么做了吧