核心畫面
You can picture unless as a single door that has to stay shut for the main thing to happen. 'I'll go unless it rains' means: the road to going is open as long as one thing — rain — does NOT happen. The moment that one condition opens the door, the main thing is cancelled. So unless is really 'except if': everything proceeds, except in the one case named.
可以把 unless 想成一道「只要不打開、主事就照常」的門。I'll go unless it rains 的意思…更多收起
可以把 unless 想成一道「只要不打開、主事就照常」的門。I'll go unless it rains 的意思是：去成的這條路一直開著，前提是「下雨」這件事不要發生；一旦這唯一的條件成立、門被打開，主事就取消。所以 unless 骨子裡就是「除了…這一種情況之外」：事情照常走，只有被點名的那一種例外會擋住它。原始詞典資料3 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
unlessconj/ənˈlɛs/
- 1
Except on a specified condition; if not.
- I’m leaving unless I get a pay rise.
- You can't go out unless it stops raining.
- 2
If not; used with counterfactual conditionals.
- Who would know of Alexander or Caesar, or would respect the Stoics or the Peripatetics, unless they had been distinguished by the memorials of writers?
- And Joab said, As God liveth, unless thou hadst spoken, surely then in the morning the people had gone up every one from following his brother.
- 3
Except if; used with hypothetical conditionals.
- Q. If Lieutenant P. had given the word "Fire," would you have fired, and at what?—A. I should not have known, unless he had told me what to fire at.
- Lie down and finish out the night, since you are here; but, for heaven's sake! don't repeat that horrid noise: nothing could excuse it, unless you were having your throat cut!
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。