Comparing "bu" and "mei"

都是否定副词，都可以用在动词前面，但是使用时间不一样。 Both 不（bù) and 没 (méi) can be placed in front of a verb or adverb to negate its meaning. 不 and 没 are some times interchangeable. However, there are times when you must use 不 as opposed to 没 and vice versa.

不-not wanting to do something

“不”一般是表达不想做的事情。 不 is generally used to express an action that you do not want to do.

Structure

Subject + 不 + V.

Examples

• 我 今天 晚上 不 吃 饭。
• 他 不 去 公园。

• 明天 我 不 在 家。
• 上周 我 不 和 我 的 朋友 在 一起。

没

“没”用于描述过去，说明动作没有发生。很多时候和“有”一起用，意思和用法不变。 没 is used to describe actions in the past or illustrate an action that hasn’t happened yet. Often times, 没 is used together with 有(yǒu) (the meaning and use do not change).

Structure

Subject + 没（有）+ V.

Examples

• 昨天 晚上 我 没 吃 饭。
• 他 没有 去 公园。

• 明天 我 没 在 家。
• 上周 我 没 和 我 的 朋友 在 一起。

没: do not have (没有）

没 can be used to negate the verb 有 to mean "do not have". You can only use 没 to convey this meaning. It is grammatically incorrect to use 不.

• 我 没有 钱。
• 我 不有 钱。

Difference between 不 and 没

没有

You can use 没 to modify 有 to mean "do not have". You can only use 没 to convey this meaning. It is grammatically incorrect to use 不

• 我 没有 钱。
• 我 不有 钱。

Other examples

As stated before, 没 is used for actions that occurred in the past or for actions that have yet to occur. 不 cannot be used to express actions that happened in the past. It can, however, be used to express actions currently happening or will happen in the future. Understanding these differences is essential for choosing which word to use in which context.

• 他 没 给 我 他 的 手机号。

In this example, the speaker's use of 没 suggests that this event happened in the past. The context of time, that is very necessary in conveying the meaning of this sentence, can only be expressed through using 没.

• 我 不 吃 肉。

In this example, the speaker is explaining that he does not each meat. By using 不, the speaker has explained that he does not presently eat meat and also implies that he will not be eating meat in the future.

Dialog

• A: 你 吃 晚饭 了 吗？
• B: 没 吃。
• A: 为什么？
• B: 因为 不 想 吃。