The most frequently used negation markers in Mandarin Chinese are bu and mei, all translated as English not. They reflect the features of grammatical category of negation in Chinese. Both bu and mei typically negate verbs and adjectives, while mei can also negate nouns indicating the inexistence of something. They are generally in the preverbal (or pre-adjective) position and it is the verb/adjective phrase that is in the scope of negation. In addition to the primary role of bu and mei as markers of negation, they often serve to identify the aspect and time frame of events.
The selection of bu and mei depends on aspectual factors, types of verbs and the point of view.
1. Bu is for negating in the past, present and future. Bu is generally used to negate an action that you do not do or do not intend to do (in the future). So expressing things like "not going to do" would be uses of bu, instead of mei. Mei, on the other hand, often negates in the past and present but never the future, so 他明天没休息(ta mingtian mei xiuxi) is a grammatically wrong sentence. Tough both bu and mei can be used in past-tense negation, they are not the same in that case, since bu indicates non-completion and mei negates the completion of events.
e.g. 他今晚吃饭。Ta jinwan chifan à 他今晚不吃饭。Ta jinwan bu chifan
He is going to eat tonightà He is not going to eat tonight.
2. Bu is also used to negate habitual actions, to express what you just aren't in the habit of doing, such as eating meat, or watching movies, and so on. This is simply done by placing bu in front of the verb. If mei is used in these cases, the sentence mean will be changed into “have not yet done” which is completely different from the original one.
e.g. 我吃肉。Wo chi rou à 我不吃肉。Wo bu chi rou
I eat meat. à I don’t eat meat.
Meanwhile, bu provides a negation for stative verbs, adjectives and auxiliary verbs, that is to say, adjectival verbs and most stative verbs are negated by bu, and they are never negated by méi. Only the stative verb you ‘to have’ may be negated by mei.
他很高。Ta hen gao à 他不高。 Ta bu gao
He’s tall. à He’s not tall.
Mei has two functions; one function is to negate the possessive verb you ‘have’, where bu is impossible. The other function of mei denies that an action has taken place or a resultative state has been achieved. This function of mei implies that mei can only be used in dynamic verbs.
我有车。 Wo you cheà我没有车。 Wo meiyou che
I have a car. à I don’t have a car.
3. Another distinction between bu and mei is about subjectivity and objectivity. When bu goes with dynamic verbs without denoting a habitual meaning, it usually negates the subjective desire or willing to do something. In the example of 我不去上学(wo bu qu shangxue. I don’t want to go to school), bu expresses the interpretation that the subject is reluctant or refuse to go to school. On the contrary, mei is used in objective narration, negating that actions or events have happened. 我没去上学 (wo mei qu shangxue; I didn’t go to school) means the action of going to school has not happened, so it is not a subjective desire.
Further discussions on bu and mei can be extended to the negation makers le and guo, or the unique A-not-A question in Chinese. (A-not-A questions are formed by reduplication of the questioned element and an infixation of the negator bu or mei between the reduplicant and the base, e.g. chi bu chi à eat not eat? )