has been done 与had been done要怎么用啊
题目
has been done 与had been done要怎么用啊
答案
has been done 与had been done要怎么用啊?
has been done 是现在完成时的被动语态.
had been done是过去完成时的被动语态.过去完成时的概念是【相对过去的某个时间更早的】【过去】
如：
The work has been done.这项工作做完了/完成了.
The work had been done before you came.这项工作【在你来之前】做完了/完成了.
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