進階 · Unit 79
假設語氣 — if 的省略
在假設語氣的句子裡省略 if 時，要把 were / had / should 拉到主詞前面形成倒裝。這常用於正式文體與書面語，意思和照樣使用 if 的句子相同。
概念說明
在假設語氣的句子裡省略 if 時，要把 were / had / should 拉到主詞前面形成倒裝。這常用於正式文體與書面語，意思和照樣使用 if 的句子相同。
A. Were + 主詞 — 假設語氣過去式的倒裝
像 If I were / If he were 這種 be 動詞的假設語氣過去式，要刪掉 if，把 Were 移到主詞前面。公式是 If I were = Were I。倒裝之後 be 動詞仍然是 were，直接放在句首。
| 有 if 的句子 | 倒裝句 |
|---|---|
| If I were you | Were I you |
| If he were rich | Were he rich |
| If it were possible | Were it possible |
| If they were here | Were they here |
- Were I in your position, I would apologize. (如果我站在你的立場，我會道歉。)
- Were she more careful, this wouldn't happen. (如果她再小心一點，就不會發生這種事。)
- Were it not so cold, we could go out. (如果沒有那麼冷，我們就可以出去了。)
B. Had + 主詞 + 過去分詞 — 假設語氣過去完成式的倒裝
像 If I had known / If she had studied 這種假設語氣過去完成式，要刪掉 if，把 Had 移到主詞前面。公式是 If I had p.p. = Had I p.p. 這樣，主要子句接的是 would / could / might + have + 過去分詞。
| 有 if 的句子 | 倒裝句 |
|---|---|
| If I had known | Had I known |
| If she had studied | Had she studied |
| If they had arrived earlier | Had they arrived earlier |
| If it had not rained | Had it not rained |
- Had I known the truth, I would have told you. (如果我知道真相，我就會告訴你了。)
- Had she taken the train, she would have arrived on time. (如果她搭了火車，就會準時抵達了。)
- Had we left earlier, we wouldn't have missed the flight. (如果我們早一點出發，就不會錯過班機了。)
- Had it not been for the delay, we would have met him. (如果沒有那次延誤，我們就會見到他了。)
C. Should + 主詞 — 未來可能性的倒裝
像 If you should ~ 這樣，要表示未來「萬一~的話」這種很低的可能性時，就把 Should 移到主詞前面。常用於正式的公告與商務文件，後面接的是命令句、建議或 please 開頭的句子。
| 有 if 的句子 | 倒裝句 | 意思 |
|---|---|---|
| If you should need help | Should you need help | 萬一需要幫忙 |
| If you should have questions | Should you have questions | 萬一有問題 |
| If anything should happen | Should anything happen | 萬一發生什麼事 |
- Should you need further information, please contact us. (如果需要更多資訊，請和我們聯絡。)
- Should you change your mind, let me know. (萬一改變心意，請告訴我。)
- Should there be any problem, call this number. (萬一有任何問題，請打這支電話。)
- Should he arrive late, we will start without him. (萬一他晚到，我們會先開始，不等他。)
重點整理
- 1在假設語氣中省略 if 時，要把 were / had / should 倒裝到主詞前面。(例: If I were → Were I)
- 2這種倒裝結構主要用在正式文體與書面語，意思和使用 if 的句子相同。會話中還是用 if。
- 3否定句裡的縮寫(wasn't / hadn't)不能倒裝，要把 not 放到主詞後面拆開來寫。(X: Hadn't I known / O: Had I not known)
- 4Should + 主詞是表示未來低可能性「萬一~的話」的正式說法，常用於公告與商務文件。(例: Should you need help)
- 5發生倒裝的是助動詞(were / had / should)，不是一般動詞。If I knew 不會倒裝，維持原樣。
例句
Were I you, I would accept the offer.
如果我是你，我會接受那個提議。
Were I in your position, I would apologize.
如果我站在你的立場，我會道歉。
Were she more careful, this wouldn't happen.
如果她再小心一點，就不會發生這種事。
Were it not so cold, we could go out.
如果沒有那麼冷，我們就可以出去了。
Had I known earlier, I would have called you.
如果我早一點知道，我就會打電話給你了。
這個單元還有更多例句。註冊後可以看完整內容並聆聽發音。
容易犯的錯誤
Were I you, I would apologize.
Had I known earlier, I would have called.
Had I not known, I wouldn't have said it.
If I knew the answer, I would tell you.
Should you need help, call me.