Bu and mei(you)

Although 不 (bù) and 没(有) (méi(yǒu)) both have the same functions of negating verbs and adjectives, they are used differently. Let's take a look at some of these differences.

有 is negated with 没

没 (rather than 不) is always used to negate 有, the verb meaning "to have." The phrase "不有" exists only in non-standard Chinese dialects, in obscure set phrases (that you don't need), and in incorrect Chinese. Keep in mind also that when 没 is used to negate 有, 有 can be dropped altogether.

• 没有
• 不 有
• 我 没有 钱。
• 我 没 钱。
• 我 不 有 钱。
• 她 没有 朋友。
• 她 没 朋友。
• 她 不 有 朋友。

Past and present statements

Perhaps the most important difference between 不 and 没(有) is that 不 negates actions and statements about the present whereas 没 negates actions and statements about the past. Note that 没(有) is used to say that something has not taken place, whereas 不 is used to say that something is not the case, or will not happen.

For example:

• 我 不 去。 I won't go; I'm not going)
• 我 没 去。 I didn't go)
• 我 没 告诉 他！ I didn't tell him)
• 我 不 告诉 你！ I won't tell you; I'm not telling you)

A few exceptions

The verb 是 is never negated with 没; it can only be negated with 不.

• 不 是
• 没 是
• 昨天 不 是 星期一。
• 昨天 没 是 星期一。
• 那个 时候，我们 不 是 朋友。
• 那个 时候，我们 没 是 朋友。

Sources and further reading

Websites

• http://www.docin.com/p-20925643.html
• http://wenku.baidu.com/view/e2e8eb2ce2bd960590c67703.html