HAVE TO or MUST

Welcome to your HAVE TO / MUST lesson! In this topic we talk about:

• When do we use HAVE TO? 

• How do we use MUST? 

• MUSTN’T and DON’T HAVE TO. 

• HAVE GOT TO. 

Take the quizzes when you’re ready! If you’re having problems, use the comment box to contact our English Teachers.

When do we use HAVE TO?

“I have to do something” means “it is necessary to do something”:

You have to turn left here.

I have to wear sunglasses when I drive.

She was quite ill, and had to go to the doctor’s.

We use modal verbs with HAVE TO in questions and negative sentences:

Did you have to wear a school uniform?

She doesn’t have to work on Tuesdays.

You can use WILL, MIGHT and MAY with HAVE TO:

If your eyes get worse, you‘ll have to go to the optician’s.

The sausages are really salty, you might have to boil them.

How do we use MUST?

MUST is similar to HAVE TO:

It’s getting late, I must go.

You can use MUST to give your own opinion. (For example, to talk about what you think is necessary, or to recommend someone do something.) HAVE TO is also possible:

I haven’t seen Mark in ages, I must call him. 
(I think this is necessary)

You must meet Mark, he’s such a nice guy.

You use HAVE TO (not MUST) to say what someone is obliged to do. The speaker is not giving their opinion:

I have to wake up early tomorrow. 
(this is a fact, not an opinion)

She has to drive to the city every day.

MUST is often used with written rules and instructions:

Applicants must attach their CV to the cover letter.

Participants must write their names in block capitals.

MUST cannot be used in the past:

We had to cancel the picnic because it started to rain.
(not “We must cancel the picnic because it started to rain.”)

MUSTN’T and DON’T HAVE TO

MUSTN’T and DON’T HAVE TO do not mean the same thing:

HAVE GOT TO

You can use HAVE GOT TO instead of HAVE TO:

I have to work tomorrow. ↔ I have got to work tomorrow.

She has to drive to the city every day. ↔ She has got to drive to the city every day.