不是…就是…bùshì... jiùshì...

Structure 不是…就是… (bùshì... jiùshì...): Either... or...

Meaning: Either A or B (if not A, then B)

Pattern

不是…就是… expresses that there are only two possibilities, A or B; if it is not A, then it must be B, with no third option.
It is very useful for expressing speculation between two options or describing two alternating habitual actions.
Unlike 不是…而是… (which negates A and affirms B — "not A, but B"), 不是…就是… keeps both A and B as valid possibilities.
Clauses A and B should have parallel grammatical structures (nouns, verbs, or clauses).
Be careful not to confuse 就是 ("then it is") with 而是 ("rather it is").

1
他每天不是看书就是写字。
Tā měitiān bùshì kàn shū jiùshì xiě zì.
Every day he is either reading books or writing characters.
2
周末我不是去逛街就是去看电影。
Zhōumò wǒ bùshì qù guàngjiē jiùshì qù kàn diànyǐng.
On weekends, I either go shopping or go watch a movie.
3
这件事不是他做的就是她做的。
Zhè jiàn shì bùshì tā zuò de jiùshì tā zuò de.
This matter was done either by him or by her.

•Distinguish clearly from 不是…而是… (which negates A and affirms B).

⚠️ Common Mistakes:

•Confusing 不是…就是… ("either... or...") with 不是…而是… ("not... but...").

•Using non-parallel structures for A and B, making the sentence disjointed.

Combine Vocabulary, Grammar, Reading Practice, Listening, Hanzi Writing, and Mock Exams at HSK 4 to master all skills together.