Modals must, have to, should

• Engels
• Middelbare school
• mavo
• Leerjaar 3

Modals

Modals of Advice, Obligation and prohibition

Listen to the songs in the next video. Make a note of the modal verbs you hear. How many do you hear? Answer in the slide after the songs.

Which modal verbs are you already familiar with?

Modals

should & shouldn't

ought to

must & mustn't 

Have to & don't have to

= Modals of advice, obligation and prohibition

Should / ought to

Form: Should (+ not) + base form of the verb

1. You give advice, or in the negative form, you advise against something.

Examples:

You should study for the test.

You should not (shouldn’t) stay up so late.

Must

Must (+ not) + base form of the verb

1. You think something is (not) necessary / important.

2. Life-saving advice (stronger than should).

3. When there is no other option – it has to be that way.

4. It is required by law or regulation.

Examples:

You must have a valid ticket in order to enter.

I must finish this essay today. I’m going out tomorrow.

Have to

Have/has to + base form of the verb

1. Someone else says it is necessary (not your own opinion).

2. It is necessary → obligation / necessity.

Examples:

Mum says I have to do the dishes.

I have to finish this essay today.

We have to hand them in tomorrow.

To clarify:

We often use must for more personal opinions about what it is necessary to do, and have to for what somebody in authority has said it is necessary to do.

Have to shows us that the obligation comes from somebody else. It’s a law or a rule and the speaker can’t change it.

Do you have to wear a uniform at your school?

John can’t come because he has to work tomorrow.

In Britain you have to buy a TV licence every year.

Obligation: Something that you need to do

Must shows us that the obligation comes from the speaker. It isn’t a law or a rule. 

I must call my dad tonight.

You must hand in your homework on Tuesday or your mark will be zero.

You must come and visit us the next time you come to London.

No obligation

We use don’t have to to show that there is no obligation. You can do something if you want to but it’s not compulsory.

It’ll be nice if you do but you don’t have to come with me if you don’t want to.

You don’t have to dress up for the party. Wear whatever you feel comfortable in.

Finally....

There’s something very important about must and have to. The positive forms are very similar in meaning, but the negative forms are completely different.

You mustn’t forget ...(don’t forget - you have no choice)

If you don't like him, you don't have to see him again. (there is no obligation to see him again, but you have a choice) (NOT You haven't to see him again)

Mustn't

Should

Have to

Call the emergency services if you have a cold 

drive on the right side of the road in the UK

use your mobile phone during an exam

show your passport or identity card to get on a plane.

be seventeen to drive a car in the UK.

complete a lot of exams, study and training to be a doctor.

arrive at the airport early in case there are delays.

show your passport or identity card to get on a plane.

always get enough sleep before driving a car.

I think people ... recycle more paper and glass.

1. have to
2. must
3. should
4. mustn't

The museum is free. You ... pay.

1. shouldn't
2. mustn't
3. don't have to
4. should

You ... park here. It's an emergency exit.

1. mustn't
2. must
3. have to
4. don't have to

You ... smoke. It's bad for you.

1. must
2. should
3. don't have to
4. shouldn't

I ... wear a uniform when I am at school.

1. must
2. have to
3. should
4. musn't

Mark's a sales representative. He ... travel a lot.

1. must
2. has to
3. should
4. mustn't