過去將來完成時用在虛擬語氣中

過去將來完成時在英語語法時態中是不經常用到的一種時態，因爲它所表示的意思也是人們不經常發生的狀態，過去將來完成時可以用在虛擬語氣中，表示與過去的事實相反。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），當然，主句謂語也可根據情況使用“should (could, might)+have+過去分詞”。例如：
1. If I'd left sooner, I'd have been on time.
要是我早點動身，我就準時到了。(但我動身太遲了)
2. If we had found him earlier we could have saved his life.
要是我們當時早點找到他的話，我們就可以救活他。(可惜我們找到他太晚了)
3. If I had known that you were coming I would have met you at the air-port.
要是我早知道你要來的話，我就會在機場接你了。
4. If he had lived, some day Michael would have done something important.
假定麥克爾當時在世的話，他本可做出了不起的事。
5. If I had known how he felt, I would never have let him adopt those children.
我要是知道他的想法，我是決不會讓他領養那些孩子的。
6. He would have forgotten the boy’s birthday if you hadn’t reminded him.
要不是你提醒他，他會忘記這男孩的生日的。
7. Our lives would have been greatly impoverished if we had not known our dear friend.
若不是得識我們這位好朋友，我們的生活一定十分不妙。
8. If we had come earlier we could have got on the bus.
要是我們當時早點來的話，我們就可以坐上公交車了。
9. If I had known how he felt, I would never have let him go to France.
我要是知道他的想法，我是決不會讓他去法國的。
10. He would have missed this party if you hadn’t reminded him.
要不是你提醒他，他會錯過這次聚會。