Unless… (除非)

Structure 除非 + sole condition，才 + result （or：除非…，否则…）

除非 (chúfēi) marks the ONLY condition under which something can happen: "unless…". It takes two closings. (1) With 才: 除非亲眼看到，我才会相信 = "I’ll believe it only if I see it myself". (2) With 否则 (or 不然): 除非你答应我，否则我不走 = "unless you promise me, I won’t leave". It stresses that there’s no other way.

Examples

除chú非fēi你nǐ答dā应yìng我wǒ，否fǒu则zé我wǒ不bù走zǒu。
Unless you promise me, I won’t leave.
除chú非fēi亲qīn眼yǎn看kàn到dào，我wǒ才cái会huì相xiāng信xìn。
I’ll only believe it if I see it with my own eyes.
除chú非fēi你nǐ跟gēn我wǒ一yī起qǐ去qù，我wǒ才cái去qù。
I’ll only go if you come with me.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

This point and the other 370, with audio on every example, inside Wanyu.