Modal Verbs in English: Modal Auxiliary Verbs

Modal verbs can be confusing for learners of English as a single modal verb can be used to express different meanings.

Modal Verbs in English

Modal verbs belong to the larger category of auxiliary verbs. These auxiliary verbs cannot be used on their own. They are used in conjunction with other (main) verbs.

What are modals? (What are modal verbs?)

Modal verbs are verbs such as may, can, must, etc. that are used with another verb (not a modal) to express permission, possibility, obligation, ability, advice, probability, criticism, suggestions, offers, etc.

Modals are also called modal verbs, modal auxiliaries, modal auxiliary verbs.

Modal Verbs List

Here is a list of modal verbs:

can
could
may
might
shall
should
will
would
must
ought to
need (to)
dare, etc.

Modal Verbs Examples

I can speak three languages.
You must respect the club’s rules.
You ought to respect the rules.
He is absent today. He may be sick.
Can I help you?
You shouldn’t eat much meat.

Tips:

Modal verbs are followed by infinitive without ‘to’ except ‘used to’ and ‘ought to’
Modal verbs have one form. They don’t have -ed or -ing forms.
Questions are not formed by the use of the auxiliaries do, does or did.
To form negative sentences with modals just use not or -n’t after the modal verb.

Can and cannot meaning (can’t)

Cannot is one word. The short form is can’t.

1. Can is used to ask permission to do something:

Can I stay out with my friends, mom?
Can I go out, please?

2. Can and cannot are used to give or refuse permission:

You can / cannot borrow my new car.
You can’t wear jeans at work. (You aren’t allowed or permitted to wear jeans at work.)

3. Can expresses an offer:

Can I help you? (what can I do for you?) (offering help)
Can I get you a glass of juice?

4. Can is used to make a request:

Can you help me?
Can you open that window, please? It’s hot in here.

5. Cannot or can’t express certainty or impossibility (deduction about present)

That can’t be Tim. He’s at school now. (I’m sure he isn’t Tim.)
Wait a minute! That can’t be true.

6. Can’t have + past participle expresses certainty or impossibility in the past (deduction about past)

She can’t have forgotten about the party.
He can’t have stolen your mobile. He’s a trustworthy person.

7. Can is used to make suggestions:

We can go together to the book fair.
We can eat out today if you like.

Could /Could Not/ Could Have (done)

Could meaning: Could has different meanings. (Could synonym)

1. Could = knew how to, was/were able to:

I could swim when I was a child.
She could ride a horse when she was 12 years old.

2. Couldn’t = wasn’t/weren’t able to:

I couldn’t attend yesterday’s meeting. I was sick.
She couldn t finish her work. She got tired.
I tried to carry that box, but I couldn’t.

3. Could is used to make a polite request:

Could you explain again?
Could you open the door, please?
Could you please pass me the salt? (= Could you pass me the salt, please?)

4. Could and couldn’t can be used in the second conditional:

If I were you, I could do this online course to improve my English.

5. Could is used to express a wish:

I wish I could come to your party. (= I want to attend your party, but I can’t)
I wish I could be there with you.

6. We also use “could” to ask for permission:

Could I use your computer?
Could I use the phone?
Could I borrow your bicycle?
Could I borrow your pen?

7. Could is used to express present and future possibility:

This letter could be from my friend, Janet. She sends me letters from time to time.

8. Could have (done) is the past of could do. We use could have (done) to say that we had the ability or the opportunity to do something but did not do it. Here are some examples:

We didn’t go out last night. We could have gone to the movies, but we decided to stay home. ( We had the opportunity to go out, but we did not).
Why didn’t Jim apply for the job? He could have got it. (He had the ability to get it.)

We also use could have (done) to say that something was a possibility but didn’t happen. Here is an example:

Janet was lucky when she fell off the ladder. She could have hurt herself.

Here is a guide to English tenses

May /may not

1. “May” is used to give permission:

You may use my computer.
You may borrow my pen.
You may smoke here.

2. “May” is used to ask for permission:

May I ask a question? Yes, of course, you may.
May I borrow your pencil?

3. “May” can express possibility in the present or future. (May = it’s likely / it is possible/perhaps)

You may buy this shirt if you like.
It may rain tomorrow.
I may be there by 7 p.m.

4. “May” can express ‘polite offer’:

May I help you with the luggage?

5. “May not” is used to express prohibition:

You may not smoke here.
You may not swim here.

Shall

We use ‘shall’ with the subject pronouns I and we to make a suggestion. Here are some example:

Shall we go?
Let’s go out for a walk, shall we?
Shall I help you?
Where shall we go this afternoon?

Tip:

We use ‘shall’ in questions with the first person singular or third person plural to make suggestions or offers as seen in the above examples.

Must / Have to / Mustn’t / Must have

1. “Must” and “have to” express obligation/necessity:

“Must” usually expresses the speaker’s opinion. We use it to speak about what the speaker thinks is necessary. On the other hand, “have to” refers to something which is necessary because of rules, laws, or regulations, or because someone else says so.

⇒ You will graduate soon. You must think about your future. (I think it’s necessary)

⇒ You have to wear a uniform at school. (It’s a rule/ a regulation)

2. The past of must is “had to”

My dad had to visit a doctor yesterday.
We had to wear uniforms when we were students.

3. “Mustn’t” is used to express prohibition:

You mustn’t smoke here. (= You aren’t allowed to smoke here.)
You mustn’t take drugs here. (Taking drugs here is forbidden)

4. Must have (done) is used to express certainty in the past.

I saw him driving his father’s car. He must have passed his driving test. (I’m sure he passed his driving test.)

Modal Verbs Exercises

Exercise 1: Fill in the gaps with appropriate modal verbs from the list.

I can’t find my mobile. I ………….have left it at home.
a. will b. might c. need
Oh my God! There is a lot of traffic again. I ….……..get to my office on time.
a. needn’t b. can’t c. mustn’t
You …….drive me to work today. I can take the bus.
b. should b. needn’t c. mustn’t
She had a terrible accident. She …………have been driving fast.
a. must b. can’t c. mustn’t
My sister ……….get the best marks when she was in the high school.
a. could b. can c. may
Tom is terribly sick. He …….…see a doctor.
a. should b. might c. shouldn’t
You …….…buy a ticket for the match. I have already bought two.
a. wouldn’t b. needn’t c. can’t
Your face is familiar to me. We ………have met before.
a. should b. must c. would

Exercise 2: Match the following sentences with the meaning they express.

Sentences with modal verbs	Functions/Meaning
1. I can speak and write Chinese.	Possibility
2. You can learn any language online.	Ability
3. We had to respect the company’s rules.
4. You must have prepared well for the test.	Obligation
5. She can’t have been at home when you called her.	Certainty
6. You’ve been traveling all day. You must be tired
7. There could be another rise in the price of gas soon.	Impossibility