除非 (chúfēi) — unless; only if; except when

除非 (chúfēi)

除非 is a conjunction meaning "unless" or "only if," used to introduce the one and only condition that would change an outcome or serve as an exception to an otherwise absolute statement.

Meanings

1. [conjunction] unless; only if; except when (introduces the single exception or the only condition under which the main clause does not apply, or under which an otherwise impossible outcome becomes possible)

Usage Note

除非 introduces a conditional clause. It works in two main patterns:

Pattern 1: 除非 + [only condition], 否则/不然 + [what happens without that condition] "Unless [condition], otherwise [negative result]."

Pattern 2: 除非 + [only condition], 才 + [result only possible with that condition] "Only if [condition], then [result] is possible."

这件事除非你亲自去，否则他不会相信。 Unless you go yourself, he will not believe it. 除非你道歉，我才能原谅你。 Only if you apologize will I be able to forgive you.

The difference from 如果 (if): 如果 is a general conditional, while 除非 marks the sole exception or the one necessary condition.

Example Sentences

除非下大雨，否则比赛照常进行。 Chúfēi xià dà yǔ, fǒuzé bǐsài zhàocháng jìnxíng. Unless it rains heavily, the match will proceed as scheduled.

除非你亲自道歉，否则我不会原谅你。 Chúfēi nǐ qīnzì dàoqiàn, fǒuzé wǒ bú huì yuánliàng nǐ. Unless you personally apologize, I will not forgive you.

除非有特别情况，他每天都按时上班。 Chúfēi yǒu tèbié qíngkuàng, tā měitiān dōu ànshí shàngbān. Unless there is a special circumstance, he comes to work on time every day.

除非你努力练习，否则你的口语不会提高。 Chúfēi nǐ nǔlì liànxí, fǒuzé nǐ de kǒuyǔ bú huì tígāo. Unless you practice diligently, your spoken language will not improve.

Collocations

Memory Hook

除 means "to exclude / to remove" and 非 means "not / wrong." 除非 removes everything except the one thing that is "not wrong" — the sole valid exception. If you exclude all others, only that one condition remains: "unless" exactly that condition.