Топик: Сравнительные степени прилагательных и наречий (Comparison) Модальные глаголы (Modal Verbs) Цепочки существительных (Атрибутивная, номинативная группа) (Chains of nouns)

In each of the above cases, the "obligation" is the opinion or idea of the person speaking. In fact, it is not a real obligation. It is not imposed from outside.

We can use "must" to talk about the present or the future. Look at these examples:

• I must go now. (present)

• I must call my mother tomorrow. (future)

There is no past tense for "must". We use "have to" to talk about the past.

Must Not (prohibition)

We use must not to say that something is not permitted or allowed, for example:

• Passengers must not talk to the driver.

Structure of Must Not

"Must" is an auxiliary verb. It is followed by a main verb. The structure for "Must Not" is:

• Subject + "Must Not" + Main Verb

The Main Verb is the base verb (infinitive without "to").

"Must Not" is often contracted to "mustn't".

Look at these examples:

NB: like all auxiliary verbs, "must" cannot be followed by an infinitive. So, we say:

• You mustn't arrive late. (not You mustn't to arrive late.)

Use of Must Not

"Must Not" expresses prohibition - something that is not permitted, not allowed. The prohibition can be subjective (the speaker's opinion) or objective (a real law or rule). Look at these examples:

• I mustn't eat so much sugar. (subjective)

• You mustn't watch so much television. (subjective)

• Students must not leave bicycles here. (objective)

• Policemen must not drink on duty. (objective)

We use "Must Not" to talk about the present or the future: