一、過去將來完成時
過去將來完成時表示從過去觀點看將來某時某動作會業(yè)已完成。這個時態(tài)用得相對比較少，通常主要用于轉(zhuǎn)述方面，即用于間接引語中。如：
The party would have arrived by four o’clock. 這一行人將于4時前到達(dá)。
She said she’d have finished her exams by then. 她說那時她會已經(jīng)考完試了。

二、構(gòu)成方法過去將來完成時
過去將來完成時由“would+have+過去分詞”構(gòu)成：should / would+ have done sth.

三、基本用法
過去將來完成時的基本用法就是：表示從過去某一時間來看將來某時會已經(jīng)完成的動作。如：
He knew by the time he arrived she would have gone home. 他知道他到時她會已經(jīng)回家。
I thought Sophia would have told you something. 我想索菲婭會已告訴你一地情況。
The day was drawing near when we would have completed the reservoir. 我們建成水庫的日子不遠(yuǎn)了。
He said he would have done with my camera by the end of next month. 他說到下月底就不用我的照相機了。

四、過去完成時用于虛擬語氣中
若表示與過去事實相反的虛擬語氣，此時條件從句的謂語用過去完成時(had+過去分詞)，而主句謂語則通常用過去完成時（would+have+過去分詞），當(dāng)然，主句謂語也可根據(jù)情況使用“should (could, might)+have+過去分詞”。如：
If I'd left sooner, I'd have been on time. 要是我早點動身，我就準(zhǔn)時到了。(但我動身太遲了)
If we had found him earlier we could have saved his life. 要是我們當(dāng)時早點找到他的話，我們就可以救活他。(可惜我們找到他太晚了)