過去(事實 / 非事實)條件句(conditional sentence)詳解，If假設語氣 Past Conditional (Real/Subjunctive)
1. 過去「事實」條件句 (Past Real Conditional)
– 過去「曾經常發生」，但現已不再。
| 句式： | |
| If / When … 簡單過去式 … , | … 簡單過去式 …… used to +v |
| 條件子句 | 主句 |
條件子句的conjunction(連接詞)可使用’if 或 when’:
– 使用 if表示某事當時「頻率一般(相對中性)」，可譯成「當時如果」；
– 使用 when表示某事當時「頻率較高(較經常)」，可譯成「當時只要」。習慣上，過去「事實」條件句多用when，較少用if。
例句：
1. When I had (簡單過去式) a holiday , I traveled (簡單過去式) to Europe each year. But this year I have no such free time.
過去只要我有假期的話，我每年都會去歐洲旅遊。但今年我卻沒有這樣的餘閒時間。【現已不再】
2. When I had (簡單過去式) my cat in the house, I used to buy (used to +v) her many healthy snacks. Yet, she has already left.
過去只要我家裡有貓，我習慣上買給她很多健康零食。可是，她已經離開了。【過去習慣，現已不再】
3. I used to ask (used to +v) the teachers for help when I was (簡單過去式) young. Now, I cannot do this in the workplace.
當我年紀小的時候，我習慣會向老師尋求幫忙。現在，我不能在職場這樣做了。【現已不能】
4. When she lived (簡單過去式) with her elder sister, she didn’t need (簡單過去式) to do any housework. Now, she has to tidy up the house once a week.
當她和姐姐住在一起時，她不需要做任何家務。現在，她不得不每週一次整理房子。【現已不再了!】
2. 過去「非事實」條件句 (Past Subjunctive Conditional)
– 與過去事實相反，具「虛擬語氣」(Subjunctive Mood)。
– 由於是Subjunctive Mood，其條件子句的時態會【向過去退一格】:〈簡單過去式〉變成〈過去完成式〉。
| 句式： | |
| If … 過去完成式 … , | … would have + ved (過去分詞) … (could have /should have/might have +Ved 也行) |
| 條件子句 | 主句 |
【重覆提示: 在「非事實」條件子句下就不能用when，只能用if 】: 原因好簡單，因為「非事實」就不可能屬經常，用if只是在作「虛擬假設」。
主句除了 would have外，還可使用 should have/could have/ might have +Ved 這三個情態助動詞在句子中。
例句：
1. If I had had (過去完成式) a daughter, I would have taught (would have +Ved) her many cooking skills.
如果我當時有一個女兒，我會教給她不少烹飪技巧。【虛擬語氣: 可惜當時沒有！】
2. If I had remembered (過去完成式) her date of birth, I would have already told (would have +Ved) you.
如果我當時記得她的生日日期，我早就告訴你了。【虛擬語氣: 可惜當時記不起！】
3. If I had had (過去完成式) a younger brother, I should have taught (should have +Ved) him Chinese Kung Fu.
如果我有一個弟弟，我應該會教他中國功夫。【虛擬語氣: 可惜我無弟弟！】
4. I could have gone (could have +Ved) to Disneyland with you, if I had finished (過去完成式) my work.
當時如果我完成工作，我定會和你一起去迪斯尼樂園的。【虛擬語氣: 可惜實在完成不了！】