had been done

基本解释

Then when I called the last time, you could have said that although everything possible had been done for Edgar, he had died.
在我最后一次给你打电话询问，你可以说尽管对埃德格做了一切所能做的努力，它还是死了。
It was the only way he could regard her mortal remains with detachment, the only way he could focus on the cold mechanics of what had been done to herbody.
只有这样他才能不带感情地对待她的遗体，也只有这样他才能全神贯注以完成这个冷酷的过程。
Instead of just piling the oysters up close to the riverbed, as had been done in the past, they built reefs of various heights above the bed for them to grow on.
他们没有按照过去通常的作法仅仅将牡蛎在靠近河岸处一层一层地摞起来，而是在河床上建造了高度各异的（供牡蛎生长的）牡蛎礁。

Earlier observations about the movement of galaxies had been done by V.M.Silpher.
It wasn't actually a study itself on the Mediterranean Diet, but it was a review of other studies that had been done using this statistical technique called meta-analysis.
该研究本身并不直接研究地中海式饮食法,而是运用荟萃分析的统计方法,对其它已有的相关研究进行研究
耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选
And how far in advance he had even been thinking about some of the stuff that he had done
他很早前就开始构思他的作品了，
和男朋友在一起 - SpeakingMax英语口语达人

By the time Downing Street had turned the heat down again, the damage had been done.
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