大学英语四级语法大全目录
1)have +过去分词,构成完成时态,例如:
He has left for London. 他已去了伦敦。
By the end of last month, they had finished half of their work.
上月未为止,他们已经完成工作的一半。
2)have + been +现在分词,构成完成进行时,例如:
I have been studying English for ten years.
我一直在学英语,已达十年之久。
3)have+been +过去分词,构成完成式被动语态,例如:
English has been taught in China for many years.
中国教英语已经多年。
From:https://www.zgghmh.com/CET-4/20001011.asp