HAVE TO CAN MUST

NAF LEVEL 2 – UNIT 4 GRAMMAR

Have to / Don’t have to• We use have to when we mean «this is

necessary» or you are «obliged to».Example:All children have to go to school in this country.

• We use don’t have to when we mean «this is not necessary» or «you are not obliged».

Example:Three-year-old don’t have to go to school.

Have to / don’t have toSUBJECT EXPRESSION VERB IN BASE FORM COMPLETMENT

I

have todon’t have to

study for the test.You pay attention in class.We practice our English.

They work every day.He

has todoesn’t have to

finish the project today.She take care of the children.

It be good. had to go to school

Questions with have toDO / DOES

SUBJECT

EXPRESSION

VERB BASE FORM

COMPLEMENT

Do Iyouwethey

have to

do the homework?

Does hesheit

clean the class?

Did Iyouwetheyhesheit

read the book?

Can / Can’t• We use can when we mean you «are

able to» or «permitted»• We use it for «permission»• We use it to express capacity to do

something.• We use can’t means «you are not

permitted» or that «you don’t have capacity to do»

Can / can’tAFFIRMATIVE NEGATIVE QUESTION

I can swim. I can’t swim. Can you swim?

You can stay at home.

You can’t stay at home.

Can I stay at home?

SHORT ANSWERS

Yes, I can. No, I can’t

Must / mustn’t

• We use must when we mean that something is very important and you are obliged to do it.• We use mustn’t when we mean

that something is «not permitted»

Must / mustn’tAFFIRMATIVE NEGATIVE SHORT

ANSWERSYou must clean your room.

You mustn’t swim without warming up. Yes, I must.

No, I mustn’t.He must respect his friends.

She mustn’t go out late.