Modal Auxiliaries Verbs (Grammar)

Topic: Grammar: Modal auxiliaries

There are 12 Modal auxiliaries verbs in English and they express a board range of meanings, including concepts and attitudes such as recommendation, obligation, necessity, prohibition, probabilit and certainty, permission and refusal, promise and intention, ability and willingness.

There are four paired auxiliary verbs forms: can,could, shall, should, will, would, may, might. There are four single forms: must ought , dare, need.

Expressing obligation and necessity

We use must plus a verb when we want to say that something is very important to do or to express something which is a rule. We use mustn’t plus a verb for something that is important not to do. Note that have to plus a verb has the same meaning as must plus a verb. However, don’t have to doesn’t have the same meaning as mustn’t. Don’t have to means it is not necessary to do something.

Examples:

. We must all be patient.

. You mustn’t talk to your brother like that.

. I have yo get up early in the morning to get ready for school.

We use should plus a verb when we want to say something is a good idea to do. We use shouldn’t plus a verb for things which are good idea not to do. Must/mustn’t are stronger thant should/shouldn’t. We also use ought to plus a verb when we want to say that something is a good idea to do and ought not plus a verb when we want to say that something is a good idea not to do.

Examples:

. You should care about what people think.

. Children shouldn’t be allowed to play in the street.

. You ought not to leave the toilet unwashed.

. You really ought to quit smoking.

We can also use the verb need to to express necessity- something which is a good idea to do. We use not need to or not have to to say that something is not necessary to do.

Examples:

. You need glasses for reading.

. You don’t really need a car.

You needn’t leave now- You can leave later.

. I don’t have to make dinner tonight.

Assignment

Choose the best answer to complete each sentence.

1. My clothes are dirty. I ……. wash them. a) needn’t b) oughtn’t to c) need to d) must

2. I have made the bed. You …… do it. a) shouldn’t b) should  c) mustn’t d) needn’t

3. You ….. talk to your brother like that. a) oughtn’t  b) must c) mustn’t d) needn’t

4. Why did you wear my dress! You …..ask before you take my things. a) has to  b) needn’t c) should d) shouldn’t

5. It’s important you go to school. And you ……be late! a) mustn’t  b)must c) ought not d) don’t have to