If I Were Rich：不用頭痛的條件句

「If I win the lottery, I will buy a house.」簡單。充滿希望。也許不太實際，但文法很整齊。

「If I won the lottery, I would buy a house.」也正確，但現在這句話戴上墨鏡，看向遠方。它感覺比較不可能，更像想像。

「If I had won the lottery, I would have bought a house.」現在樂透已經結束，彩券很哀傷，房子仍然只是理論。

Conditionals 是英文談論原因、可能性、想像、後悔、建議，以及我們每天隨身攜帶的小型平行宇宙的方式。它們看起來複雜，是因為動詞形式會移動。但每一次移動都有目的。

快速答案

一個 conditional sentence 通常有兩個部分：

• if clause：條件
• main clause：結果

例子：

• If it rains, we will stay inside.

If it rains 是條件。We will stay inside 是結果。

最常見的模式如下：

你不需要先背名稱。先從真實程度開始：事實、真實可能、想像、後悔，或混合結果。

模式

條件句不是隨機的。它們是一台距離機器。

情況越不真實，動詞就越往後退。

• 真實現在/未來：If I have time, I will help.
• 想像現在/未來：If I had time, I would help.
• 想像過去：If I had had time, I would have helped.

注意，「past」形式不一定表示過去時間。在 second conditional 裡，had 常常表示和現實有距離。

• If I were taller, I would reach the shelf.

說話者不是在說「我昨天比較高」。他是在想像一個不同的現在。

對 be 來說，許多謹慎的說話者會在想像條件句中對所有主詞使用 were：

• If I were rich, I would travel more.
• If she were here, she would know what to do.

日常口語中，你可能會聽到 was，尤其搭配 I 或 he/she/it。但在正式寫作和考試中，were 更安全。

一個好習慣是把時間和真實程度分開看。If clause 中看起來像過去的動詞，可能表示過去時間，也可能表示和現實的距離。在 If I had a car 裡，had 不是在講過去故事，而是在想像一個不同的現在。在 If I had had a car yesterday 裡，多出的 had 把條件推進不真實的過去。形式會變，是因為想像世界離現實更遠了。

自然例句

Zero conditional：事實與規則

用 zero conditional 表示普遍成立的事情。

• If water freezes, it expands.
• If you press this button, the screen turns on.
• If employees miss the deadline, the system sends a reminder.
• If I skip breakfast, I get hungry by ten.

模式：

If + present, present

這不是在說某個特別的未來事件，而是一個規則、習慣或可靠結果。

First conditional：真實的未來可能

用 first conditional 表示現實中可能發生的未來情況。

• If it rains tomorrow, we will move the picnic indoors.
• If the client approves the draft, we will publish it Friday.
• If you finish early, you can leave early.
• If I see her, I will ask.

模式：

If + present, will / can / may / might + verb

重點：if clause 使用現在式，即使意思是未來。

• If I will see her, I will ask.
• If I see her, I will ask.

Second conditional：想像中的現在或不太可能的未來

用 second conditional 表示想像、不太可能或不可能的情況。

• If I had more time, I would exercise more.
• If we owned a bigger office, we could host the event here.
• If the app were faster, more people would use it.
• If I found a wallet on the street, I would take it to the front desk.

模式：

If + past, would / could / might + verb

這個模式也很適合用來給建議：

• If I were you, I would ask for clarification.

意思是「如果我在你的情況，我的建議是……」

Third conditional：想像中的過去

用 third conditional 表示沒有發生的過去情況，以及想像中的結果。

• If I had studied more, I would have passed.
• If they had left earlier, they would not have missed the train.
• If we had checked the address, we would have found the building faster.
• If she had saved the file, she would not have lost the draft.

模式：

If + past perfect, would / could / might have + past participle

這是後悔、鬆一口氣、批評與偵探推理的文法。

Mixed conditional：過去原因，現在結果

有時過去事件會影響現在。

• If I had gone to bed earlier, I would not be so tired now.
• If he had taken the job, he would live in another city now.
• If we had invested in better tools, the team would be faster today.

模式：

If + past perfect, would + verb

條件在過去，結果在現在。

你也可以把句子順序反過來，意思不變：

• I would not be so tired now if I had gone to bed earlier.
• The team would be faster today if we had invested in better tools.

if clause 放在前面時，通常會有逗號。結果放在前面時，通常不加逗號。文法相同，只是句子的路線不同。

常見陷阱

陷阱 1：在 if clause 裡使用 will

一般 first conditional 中，不要在 if 後面用 will。

• If it will rain, we will stay home.
• If it rains, we will stay home.

有些特殊情況中 will 表示意願，但基本未來條件句用現在式。

陷阱 2：把 second conditional 當成普通過去式

• If I had a car, I would drive there.

這不一定表示過去。它通常表示「我現在沒有車」或「我在想像自己有車」。

陷阱 3：third conditional 忘記 have

• If I had known, I would called you.
• If I had known, I would have called you.

would have 後面接 past participle。

陷阱 4：混合真實與不真實形式

• If I win, I would celebrate.

這混合了 first 和 second conditional。選定真實程度：

• If I win, I will celebrate.
• If I won, I would celebrate.

陷阱 5：以為 if 一定要放前面

結果可以先出現：

• We will stay inside if it rains.
• I would travel more if I had more money.

if clause 放後面時，通常沒有逗號。

錯誤 / 更好 / 原因

小練習

選出最合適的形式。

1. If I _____ the password, I will log in.
   a. know
   b. will know
   c. knew

2. If she _____ more free time, she would join us.
   a. has
   b. had
   c. will have

3. If we had booked earlier, we _____ better seats.
   a. would get
   b. will get
   c. would have gotten

4. If the printer _____ paper, it stops automatically.
   a. runs out of
   b. will run out of
   c. had run out of

5. If I had taken a break, I _____ so tired now.
   a. would not be
   b. would not have been
   c. will not be

6. If I were you, I _____ the instructions again.
   a. read
   b. will read
   c. would read

答案

1. a. know - 真實未來條件在 if clause 中用現在式。
2. b. had - 這是想像中的現在情況。
3. c. would have gotten - 這是不真實的過去結果。
4. a. runs out of - 這是一般規則，所以用 zero conditional。
5. a. would not be - 過去條件、現在結果：mixed conditional。
6. c. would read - 「If I were you」給建議時搭配 would + verb。

超短總結

Conditionals 是現實設定。Zero conditional 給規則。First conditional 談真實的未來可能。Second conditional 想像不同的現在或不太可能的未來。Third conditional 想像不同的過去。Mixed conditional 把不同的過去連到不同的現在。情況越不真實，動詞通常就往後退一步。這不是混亂，而是英文禮貌地打開通往另一個事件版本的門。