英文文法(過去完成式和未來完成式)

您好,
完成式有分成三種,現在完成,過去完成,未來完成
Have + 過去分詞p.p

現在完成式:表示發生在過去的,正確的時間不重要,所以不需將時間表現出來
例句:
I have already eaten.
我已經吃完飯了

過去完成式:表示在過去的某個時間之前,要完成某件事,
例句:
I had already eaten when my friend arrived.
當我朋友到達時,我已經吃完飯了(had 和 arrived都用過去式)

未來完成式:表示在未來的某個時間前,會將某件事完成
例句:
I will already have eaten when my friend arrives
當我朋友到達時,我將吃完飯(will表未來,arrive用動詞原形)

希望能夠解答您的疑惑

為什麼不閱讀文法書或網搜該二關鍵詞呢?

過去完成式:
1.表示某事發生在過去其他事件或時點之前,

I had never seen such a beautiful beach before I went to Hawaii.

2.與非連續動詞〈have擁有,live,work,teach等〉併用，表示過去事件一直延續到過去其他事件時

we had had that car for seven years before it broke down.

未來完成式 :
1.表示在未來某時點前完成動作

by next Monday,I will have received your letter.
=by next Monday,I am going to have received your letter.

2.用未來完成式 指出某事件發生至未來

I will have been in Taipei for two months by the time I leave.
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