HSK 3 grammar · conjunction
不是…就是
不是…就是… — if not … then … (one of two)
Pattern
+ + +
( ) can be left out · other words may come before, between and after
How it works
不是 A 就是 B says the truth is one of two options — "if it's not A, then it's B". It presents two possibilities and claims one of them must hold. Do not confuse it with 不是…而是 ("not A but B").
Examples
他每天不是看书就是上网。
Tā měitiān bú shì kàn shū jiù shì shàngwǎng.
Every day he's either reading or online.
这么晚还不回来，不是堵车就是加班。
Zhème wǎn hái bù huílái, bú shì dǔchē jiù shì jiābān.
So late and still not back — it's either traffic or overtime.
周末我不是在家就是在图书馆。
Zhōumò wǒ bú shì zài jiā jiù shì zài túshūguǎn.
On weekends I'm either at home or at the library.
Related
See it in a story
In the app, 不是…就是 is underlined wherever it appears in the stories you read, and practised with sentences from them. Free.