不 (bù / bú) — not, no (negation)

HSK 1 | adverb | negates verbs and adjectives for present, future, or habitual

不 (bù / bú)

The primary negation word in Chinese. 不 negates actions in the present or future, habitual behaviors, states, and adjectives. It is pronounced bù in most contexts but changes to bú before fourth-tone syllables (tone sandhi).

Meanings

  1. [adverb] Not. Negates verbs, adjectives, and auxiliary verbs in present, future, or general statements.

不 vs. 没: the critical distinction

This is the most important grammar point for 不.

  • Use to negate present or future actions, habits, states, and adjectives.
  • Use to negate past completed actions or the verb 有 (to have).
Correct Incorrect Reason
我不吃肉。(I don't eat meat.) 我没吃肉。(would imply "I didn't eat meat" in the past) 不 for habit
我没吃早饭。(I didn't eat breakfast.) 我不吃早饭。(would mean "I don't eat breakfast" as a habit) 没 for past event
我不高兴。(I am not happy.) 我没高兴。(ungrammatical) 不 for adjectives

Example Sentences

我不喝咖啡。 Wǒ bù hē kāfēi. I don't drink coffee. (habitual)

今天我不去学校。 Jīntiān wǒ bù qù xuéxiào. I am not going to school today. (present/future plan)

她不高兴。 Tā bù gāoxìng. She is not happy. (state/adjective)

我不是学生。 Wǒ bú shì xuésheng. I am not a student. (identity statement; tone changes to bú before shì)

Collocations

Collocation Meaning
不好 not good
不是 is not
不去 not going
不知道 don't know
不客气 you're welcome (lit. don't be polite)

Memory Hook

不 is the default "no" for ongoing reality. If you are describing what something IS or IS NOT right now or in general, use 不. Save 没 for looking back at a past event. When in doubt about habits and states, 不 is correct.