不是⋯⋯就是⋯⋯ (only two possibilities)

• Pinyin: bùshì...jiùshì
• Formation: 不是 + A ，就是 + B
• Hanzi breakdown: 就 = 京 (capital) + 尤 (especially) — then/precisely

Meaning

The pattern 不是⋯⋯就是⋯⋯ (bùshì...jiùshì...) presents two and only two possibilities, meaning 'if it's not A, then it's B.' It implies that there are no other options beyond these two.

This pattern is used when the speaker believes only two outcomes, identities, or situations are possible. It frequently appears in descriptions of habitual behaviour, binary choices, or process-of-elimination reasoning. Unlike 或者⋯⋯或者⋯⋯, which presents options neutrally, 不是⋯⋯就是⋯⋯ carries a stronger sense of exhaustive enumeration — these are the only two possibilities. The tone can range from neutral observation to mild complaint, especially when describing someone's repetitive habits. In more formal contexts, 要么⋯⋯要么⋯⋯ serves a similar function but sounds more deliberate and decisive.

Examples

1. 他每个周末不是在加班，就是在准备下周的方案。 Every weekend he's either working overtime or preparing next week's proposal.
2. 这条路不是在修路，就是在堵车，从来没顺畅过。 This road is either under construction or jammed with traffic — it's never been smooth.
3. 她周末不是去图书馆，就是去咖啡馆写论文。 On weekends, she's either at the library or at a café writing her thesis.

Usage Guide

Context: spoken, written, everyday

Tone: observational

Do Say

• 他打电话的时候不是在抱怨工作，就是在说邻居的闲话。
• 每次聚餐点菜，她不是嫌辣，就是嫌油腻。
• 那家店不是排队排到门外，就是东西已经卖完了。

Don't Say

• 不是苹果，就是橘子，就是香蕉。 (The pattern strictly pairs two alternatives — adding a third 就是 clause is ungrammatical; use 要么⋯⋯要么⋯⋯ for three or more options) → 要么是苹果，要么是橘子，要么是香蕉。
• 这件事不是是好事就是是坏事。 (不是 and 就是 already contain 是 — do not add an additional 是 before the complement) → 这件事不是好事，就是坏事。

Origin & History

This construction combines 不是 (is not) with 就是 (then is), forming an exhaustive binary pattern. The logic mirrors a process of elimination — by negating one possibility, the other must be true. It has been a staple of colloquial Mandarin for centuries.

Cultural Context

Generation: All ages

Social background: Universal