What Is a Modal Verb? | Definition & Examples

Verbs updated on  February 5, 2024 5 min read
Modal verbs (aka modal auxiliary verbs) are used alongside the main verb to provide additional context regarding possibility, intention, permission, or obligation.

For example, “will” is a modal verb that indicates a person’s intention to do something or that something is certain or expected to happen. It’s used to form the future tenses (e.g., “we will be there soon”).

Examples: Modal verbs in a sentence
I can read Korean.
You must look both ways when crossing the road.
Amir might bring some snacks.

How are modal verbs used in sentences?

Modal auxiliary verbs come before the main verb in a sentence and provide additional context regarding the possibility of something or a person’s control over something. They don’t change their form (e.g., for subject-verb agreement), and the main verb is usually in the infinitive form.

Examples: How to use modal verbs
You should think before you speak.
This may be the best movie I’ve ever seen.
We will visit Maurice on the way to the grocery store.

Most modal verb meanings can be divided into two categories:

  • Possibility (likelihood and ability)
  • A person’s control over something (intention/volition, obligation/necessity, requests, permission, offers, and suggestions)
The same modal verb can have different meanings depending on the context. For example, “may” can be used both for permission and likelihood.

This list contains all the modal auxiliary verbs and their most common uses with examples.

Modal verb

Use

Example

Can

Permission Request Ability (present and future) Possibility—something we believe is usually but not always true (present and future)

You can come too if you like. Can you pass the salt? I can play the accordion. Dogs can be very loyal.

Could

Permission Request Possibility—possible but uncertain or unknown Ability (past and future)

Could I come? Could you pass the salt? My father could know. I could skate when I was young.

May

Permission (formal) Possibility—possible but uncertain or unknown

You may leave. My father may know.

Might

Permission/request (very formal) Possibility—possible but uncertain or unknown

Might I take your name? My father might know.

Must

Obligation—a requirement or command Possibility—strongly expected but not certain

You must submit your paper by November 7th. You must be very proud.

Shall

Can be used in place of “will” in future tenses (usually for human subjects) Offer or suggestion Obligation or command

I shall give her a piece of my mind. Shall I start the movie? You shall listen when I speak.

Should

Possibility—likely or expected without being certain Obligation—something that is preferable or expected but isn’t necessarily required or done Advice or suggestion

They should arrive any minute. People should brush their teeth twice a day. You should come to the party.

Will

Future tenses: Possibility (certain or expected to happen) Intention/volition Request


They will arrive at 8 o’clock. I will tell him what I think. Will you marry me?

Would

Request Volition (past, usually negative) Talking about the future in the past Conditionals and hypothetical scenarios Past habits Softening an opinion or a suggestion to make it less direct or more polite

Would you pass the salt? He wouldn’t pass the salt.
I thought he would be there.
I would stop if I were you. We would talk every night. I would suggest a different size.

The three primary auxiliary verbs (aka helper verbs) are “be,” “do,” and “have.” They are used alongside the main verb to change its tense, mood, or voice and need to be conjugated for tense and subject-verb agreement.

Examples: Auxiliary verbs in a sentence
Allan is riding a bike.
Serena didn’t like waiting.
Tianna had worked at the company for three years.

Modal verbs also appear alongside main verbs to provide additional context, so they are also known as modal auxiliary verbs. They don’t change their form.

Modal verbs can be used with auxiliary verbs to change the tense.

Even though main verbs following modal verbs are usually in their base form, when a modal verb is followed by an auxiliary verb, the main verb uses the past participle or present participle form.

Examples: Modal and auxiliary verbs combined
You should check the instructions.
You should have checked the instructions.

We might go by train.
We might be going by train.

Other modal expressions

There are other modal expressions (sometimes called phrasal modals, semi-modals, or semi-auxiliaries) that have characteristics of both auxiliary verbs and modal verbs.

While modal verbs don’t change their form, phrasal modals are often based on an auxiliary verb or a normal verb and change their form accordingly. They usually express similar meanings to modal verbs (e.g., possibility and obligation), and always precede the main verb.

Examples: Phrasal modals vs modal verbs
I am going to buy a new car.
I will buy a new car.

We have to call them tomorrow.
We must call them tomorrow.

The grammatical mood (aka modality) of a verb or sentence indicates the attitude or intention of the speaker.

In some languages, verbs will take different forms to indicate different moods. In modern English, however, the same verb form can be used for different moods, and moods are often expressed through constructions. These can include auxiliary verbs and modal verbs, which can change the mood of a sentence by expressing the possibility or necessity of something, for example.

Mood

Intention

Example

Indicative

Make a factual or neutral statement Ask a question (interrogative) State a condition (conditional)

We are watching a movie. Does Jamie like dogs? We can go home if you’re tired.

Imperative

Make a demand or request

Don’t tell her what I said.

Subjunctive

Express a wish, demand, suggestion, doubt, or hypothetical scenario

I think that you should rest.

Note
Subjunctive meanings are often expressed by modal verbs instead of subjunctive mood constructions:

It is necessary that students wear the proper uniform.
Students must wear the proper uniform.

Some languages have other moods, such as the potential mood to indicate the probability of something, that are only expressed through modal verbs in English.

More advice on using modal verbs

Below are a few pointers on using modal verbs in the following scenarios:

In indirect speech

When reporting what someone else has said, “can” and “will” may become “could” and “would” as the reported speech took place in the past. Other modal verbs will stay the same.

Examples: Modal verbs and reported speech
Andrew said “you can call me later.”
Andrew said I could call him later.

Mom said “you should do your homework.”
Mom said I should do my homework.

In negative statements

To make a negative statement containing a modal verb, add the adverb “not” after the modal verb and before the main verb (the exception is “can,” which becomes “cannot” instead of “can not”). The modal verb and “not” is often contracted (e.g., “can’t”).

Examples: How to use modal verbs in negative statements
You shouldn’t listen to them.
That mightn’t be the best idea.

For emphasis

You can place emphasis on a modal verb to contradict a statement or question. It’s often italicized in writing.

Examples: Modal verbs emphasizing a statement
You won’t even be there.
I will be there.

You can’t dance.
I can dance.

Do you want to know more about commas, parts of speech, email, or other language topics? Check out some of our other language articles full of examples and quizzes.


Verbs

Nouns

Rhetoric

Present participle

Concrete noun

Oxymoron

Linking verb

Common noun

Double entendre

Participial phrase

Abstract noun

Sibilance

Simple present tense

Proper noun

Cliché

Past progressive tense

Appositive

Paraprosdokian


Frequently asked questions about modal verbs

Is it “would of” or “would have”?

Although “would of” is sometimes used in colloquial speech, the correct form is “would have” or the contraction “would’ve” (which can sound very similar to “would of” when spoken).

“Would” is a modal auxiliary verb and “have” can either be an auxiliary verb or a main verb. Modals and auxiliaries are used with a main verb to change its tense, mood, or voice.

When “would have” modifies a main verb, it often describes a conditional or hypothetical scenario in which something didn’t happen but could have happened if the situation had been different (e.g., “we would have gone to the beach if the weather was nicer”).

What does “may” mean?

“May” is a modal verb that modifies the main verb to express either possibility or permission.

You can use “may” in formal situations to ask for or give permission (e.g., “May I borrow your pen?” “You may leave now”).

You can also use “may” to talk about something that is possible but uncertain or unknown (e.g., “the shop may be shut already”).

Tags

Sophie Shores

Sophie has a BA in English Literature, an MA in Publishing, and a passion for great writing. She’s taught English overseas and has experience editing both business and academic writing.

Great! You've successfully subscribed.
Great! Next, complete checkout for full access.
Welcome back! You've successfully signed in.
Success! Your account is fully activated, you now have access to all content.