What Is a Modal Verb? | Definition & Examples
A modal verb (also called a modal auxiliary verb) is used along with a main verb to express possibility, ability, permission, or necessity. For example, in the statement “you must leave,” “must” is a modal verb indicating that it’s necessary for the subject (“you”) to perform the action of the verb (“leave”).
The modal verb “will” is used to form the future tense, indicating an action that has not yet occurred (e.g., “I will clean the garage”).
How are modal verbs used in sentences?
Modal verbs are used along with a main verb to indicate ability, necessity, possibility, and permission. In sentences containing modal verbs, the main verb typically takes the infinitive form. Modal verbs come before main verbs and never change form.
Modal verbs list
Below is a table that illustrates some of the various uses of modal verbs. Note that modal verbs are very commonly used in a wide variety of senses—this table doesn’t cover every possible usage.
Modal verb | Function | Example |
---|---|---|
Can | Indicate ability
Indicate possibility Indicate permission (informal) Make a request (informal) |
Javi can play the guitar.
We can drive or walk. You can borrow that book. Can I have some water? |
Could | Past form of “can”
Indicate possibility Make a polite request |
She could speak French.
You could become a chef. Could you tell me the time? |
May | Indicate possibility
Indicate permission (formal) Make a request (formal) |
Dana may arrive late.
You may enter. May I respond? |
Might | Indicate possibility | I might order pizza. |
Must | Indicate obligation
Indicate likelihood |
Cyclists must wear helmets.
You must be very proud. |
Shall | Indicate a future action (normally used only with “I” and “we”)
Ask a question (normally used only with “I” and “we”) |
I shall attend.
Shall we arrange a meeting? |
Should | Make a suggestion
Indicate likelihood |
You should watch that film.
Tom should be at the office. |
Will | Indicate a future action or event
Make a polite request |
Fay will book the venue.
Will you get the door? |
Would | Past form of “will”
Make a polite request |
She would often work late.
Would you call back later? |
Modal verbs and auxiliary verbs
Modal verbs are classed as a type of auxiliary verb. Auxiliary verbs are used along with a main verb to express tense, mood, or voice. However, unlike modal verbs, regular auxiliary verbs follow subject-verb agreement and must be conjugated for tense and mood.
Modal verbs can be used along with auxiliary verbs to refer to possible past, continuous, or future action.
When a modal verb is followed by another auxiliary verb (e.g., “have,” “be”), the main verb takes either the past participle form (typically ending in “-ed,” “-n,” or “-t”) or the present participle form (ending in “-ing”).
The modal verb “will” is used in all aspects of the future tense (e.g., “I will talk,” “you will be traveling”).
Modal verbs and mood
The grammatical mood of a verb indicates the intention of the sentence. Modal verbs and auxiliary verbs are used along with a main verb to express mood.
Grammatical mood | Function | Example |
---|---|---|
Indicative | State a fact | “Lana is drinking coffee.” |
Imperative | Express a command or a request (often with a negative auxiliary verb) | “Don’t forget to call.” |
Interrogative | Ask a question | “Would you open the window?” |
Conditional | Express a condition | “You should leave now if you want to get the bus.” |
Subjunctive | Express a wish, doubt, or hypothetical situation | “If you were free, we could watch a movie.” |
Other uses of modal verbs
Modal verbs have various other functions in English. They can also be used:
Indirect speech
Modal verbs are used in indirect speech to indicate what someone else said. While most modal verbs stay the same when used in indirect speech, the past form of some modal verbs is used instead (e.g., “can” becomes “could”).
Negative statements
In negative statements containing modal verbs, the adverb “not” comes immediately after the modal verb and before all other verbs. The negative form is often contracted (e.g., “would not” becomes “wouldn’t”).
Emphasis
In everyday conversation, people sometimes place emphasis on a modal verb to refute a previous statement or question. The emphasized word is often italicized when written down.
Other interesting language articles
If you want to know more about commonly confused words, definitions, common mistakes, and differences between US and UK spellings, make sure to check out some of our other language articles with explanations, examples, and quizzes.
Frequently asked questions
- What are modal verbs?
-
Modal verbs (also called modal auxiliary verbs) are used along with a main verb to express ability, possibility, necessity, and permission. They are a type of auxiliary verb.
For example, in the statement “I can drive,” “can” is a modal verb indicating that the subject (“I”) has the ability to perform the action of the verb (“drive”).
- Is it “would of” or “would have”?
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“Would” is a modal verb that’s often used along with the auxiliary verb “have” to indicate that something was possible in the past but no longer is (e.g., “She would have been a professional athlete if she hadn’t broken her leg”). It can be contracted to “would’ve.”
People sometimes mistakenly write “would of” because of its similar pronunciation. However, “would of” is never correct.
- What does “may” mean?
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“May” is a modal verb used to indicate possibility (e.g., “I may miss the bus”), make a request (e.g., “May I have a drink?”), or indicate permission (e.g., “You may sit down”).
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