| has done是现在完成时态，且主语是单数第三人称，比如，He has finished his homework now,so his mother allows him to play outdoors.had done是过去完成时态，主语任意皆可 比如He had finished his homework yesterday afternoon,so his mother allowed him to play outdoors.being done是现在进行时态的被动语态，意为“正被……”比如：The building is being built now by the government .be done是被动语态，比如：The classroom needs to be cleaned.have been done是现在完成时的被动语态 比如：These classrooms have been cleaned ,you can do something else .had been done是过去完成时的被动语态 ，用于过去时态，跟现在完成时的被动语态用法一样 |
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