have been done 与 having been done 与have been doing与having been doing有什么区别
人气：383 ℃ 时间：2019-08-18 04:36:41
解答
have been done
已被做完
having been done
是上面的现在分词短语.
have been doing
在过去动作开始一直在进行着.
having been doing
是上面的现在分词短语.
明了吧.
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