ESL Resources for Students & Teachers - Simple English News

Grammar: Modal Auxiliaries: CAN, MUST, MAY, NEEDN’T

223

CAN

Full form                     Negative                     Negative – short form

I can come.                  I cannot come.              I can’t come.

Question

Can I come?

The same forms are used for other persons: (you, he, she, it, we, they)

Use:

can relates to ability

I can do it.

She can come at 8 p.m..

Can they carry it?

They can swim.


MUST

Full form                     Negative                     Negative – short form            Question

I must come.                 I must not come.           I mustn’t come.                            Must I come?

The same forms are used for other persons: (you, he, she, it, we, they)

Use:

must in positive sentences and questions means a duty or obligation, but in a negative statement it means a negative order

I must do it now.

Must they do their homework now?

We mustn’t forget to send those letters.

–  must in addition to its first meaning could also have a meaning of a probability, and in this case the past tense is created as follows: must + have + past participle

He must know it. (He probably knows it.)

He must have known about it. (He probably knew about it.)

MAY

Full form                     Negative                     Question

I may come.                 I may not come.            May I come?

The same forms are used for other persons:(you, he, she, it, we, they)

may relates mainly to permissions (especially in questions)

May I come in?

May he play with their toys?

– in addition to its original meaning, may can also relate to slight probability; in this case its past tense is created as follows: may + have + past participle

He may bring it. (He will bring it, perhaps.)

He may have brought it. (Perhaps he brought it.)

NEED NOT, NEEDN T

I (you, he, she, it, we, they) needn’t go there.

needn’t (need not) has the same form for all persons and relates to an absence of obligation

You needn’t go there.

They needn’t  do it now.

She needn’t help me.

Comments