have been 和 had been文法和用法? - Yahoo!奇摩知識+

(1) have been 和 had been用法和意思? 差在哪邊呢?(2) 那和過去式的 was, had 的用法又差在哪 ... have been是現在完成式，had been是過去完成式，差別在那個事實是否持續到現在。例如He have been my teacher since 2000.

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