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