Connect
To Top

English Modal Verbs

English Modal Verbs

Modal verbs are a type of auxiliary verb that express modality in the English language. Modality is the grammaticalized expression of the subjective attitude of the speaker, which includes opinions about possibility, probability, necessity, obligation, permissibility, ability, desire, and contingency. The nine English modal auxiliary verbs are:

  • can
  • could
  • may
  • might
  • must
  • shall
  • should
  • will
  • would

The following sections explain and exemplify the grammar of the nine modal auxiliary verbs including the position of modal verbs in verb phrases in English and provide the most common semantic and pragmatic meanings and uses of the nine modal auxiliary verbs.

Neutralization and Defectiveness of Modal Verbs

Unlike prototypical English verbs, modal verbs are both neutral and defective. The neutralization of modal verbs refers to the fact that modal verbs lack a separate third person singular simple present tense form. To form the simple present of most English verbs for third person singular subjects, the suffix -s or -es is affixed to the end of the base form of the verb. For example:

  • cry – cries
  • eat – eats
  • help – helps
  • march – marches
  • swallow – swallows
  • wish – wishes

Modal verbs lack a third person singular simple present form. For example:

  • can – *cans
  • could – *coulds
  • may –  *mays
  • might – *mights
  • must – *musts
  • shall – *shalls
  • should – *shoulds
  • will – *wills
  • would – *woulds

Similarly, the defectiveness of modal verbs refers to the fact that modal verbs lack non-tensed forms. Prototypical English verbs have four to six forms depending on the regularity of irregularity of the verb. The forms of a prototypical verb are a base form, an infinitive, a present participle, a past participle, a simple present form, a third person singular simple present form, and a simple past form. For example:

  • become – to become – becoming – become – become – becomes – became
  • cut – to cut – cutting – cut – cut – cuts – cut
  • drink – to drink – drinking – drunk – drink – drinks – drank
  • hire – to hire – hiring – hired – hire – hires – hired
  • meet – to meet – meeting – met – meet – meets – met
  • talk – to talk – talking – talked – talk – talks – talked

Modal verbs lack all but a base form. For example:

  • can – *to can – *canning – *canned – *can – *cans – *canned
  • could – *to could – *coulding – *coulded – *could – *coulds – *coulded
  • may – *to may – *maying – *mayed – *may – *mays – *mayed
  • might – *to might – *mighting – *mighted – *might – *mights – *mighted
  • must – *to must – *musting – *musted – *must – *musts – *musted
  • shall – *to shall – *shalling – *shalled – *shall – *shalls – *shalled
  • should – *to should – *shoulding – *shoulded – *should – *shoulds – *shoulded
  • will – *to will – *willing – *willed – *will – *wills – *willed
  • would – *to would – *woulding – *woulded – *would – *woulds – *woulded

* An asterisk indicates an incorrect form.

The Position of Modal Verbs in Verb Phrases

Like other auxiliary verbs, modal verbs appear before the head of the main verb functioning as the predicate. However, unlike other auxiliary verbs, the modal verb always appears at the beginning of the verb phrase in the initial position. For example:

  • simple active → modal + base – will study
  • perfect active → modal + have + past participle – will have studied
  • progressive active → modal + be + present participle – will be studying
  • perfect-progressive active → modal + have + been + present participle – will have been studying
  • simple passive → modal + be + past particle – will be eaten
  • perfect passive → modal + have + been – past participle – will have been eaten
  • progressive passive → modal + be + being + past participle – will be being eaten
  • perfect-progressive passive → modal + have + been + being + past participle – will have been being eaten

Grammatical Function

Modal verbs perform the grammatical function of modal within verb phrases functioning as predicates. A modal is a word that expresses modality. Modality is the grammaticalized expression of the subjective attitudes and opinions of the speaker including possibility, probability, necessity, obligation, permissibility, ability, desire, and contingency. As a semantic-grammatical category concerned with the status of the proposition that describes the event expressed by an utterance, modality might also be construed as the relativization of the validity of sentence meanings to a set of possible worlds or ways in which people could conceive the world to be different. In other words, modality allows language users to express what is, what would be, what may be, and what should be.

Semantics and Pragmatics

Modal verbs are a distinct set of verbs unique to Germanic languages and to Modern English especially that differ from prototypical verbs in form and function. Although the meanings of the nine modal verbs are numerous and nuanced, discover the most common definitions with examples.

Can

The modal verb can primarily expresses ability, permission, possibility, contingency, and requests. For example:

  • Some midwives can attend home births. (ability)
  • This patron can borrow that reference book. (permission)
  • Your son can start kindergarten in the fall. (possibility)
  • You can borrow my car if you fill up the tank with gas. (contingency)
  • Can you buy some more toilet paper?  (request)

More specifically:

  1. Expresses ability

She can run ten miles. (Having the power, ability, or capacity, she is able to run a mile.)

  1. Expresses permission

He can go to the party. (He has permission to go to the party.)

  1. Expresses possibility

You can substitute Greek yogurt for sour cream. (Substituting sour cream is possible with Greek yogurt.

  1. Expresses contingency

If he can bring the steak, then she will provide the condiments. (Her providing the condiments in contingent on him bringing the steak.

  1. Expresses requests

Can you close the window? (I am requesting that you close the window.)

Could

The modal verb could primarily expresses ability, permission, suggestions, possibility, probability, and requests. For example:

  • He could never ride a bike. (ability)
  • You could have borrowed our ladder. (permission)
  • You could check for the book at the library. (suggestion)
  • My contact could have fallen down the drain. (possibility)
  • The car could catch fire at any moment. (probability)
  • Could you pick up a DVD on your way home? (request)

More specifically:

  1. Expresses ability, specifically past ability

The old woman could play the drums. (The old woman used to be able to play the drums.)

  1. Expresses permission

You could have borrowed my shoes. (It was permissible for you to borrow my shoes.)

  1. Expresses suggestions

You could comb your hair once in a while. (I am suggesting that you comb your hair once in a while.)

  1. Expresses possibility and to a lesser extent probability

The package could have ended up in Texas. (It is possible for the package to have ended up in Texas.)
Unattended campfires could start a forest fire. (It is probable that unattended campfires will start a forest fire.)

  1. Expresses requests

Could you pass the potatoes? (I am requesting that you pass the potatoes.)

May

The modal verb may primarily expresses possibility, probability, permission, and requests. For example:

  • She may take a calculus class in the spring. (possibility)
  • It may rain tonight. (probability)
  • Your sister may borrow my dress. (permission)
  • May we go to the zoo this weekend? (request)

More specifically:

  1. Expresses possibility

Your son may fail the exam. (It is possible that your son will fail the exam.)

  1. Expresses probability

The library may charge a fine for the overdue book. (It is probable that the library will charge a fine for the overdue book.)

  1. Expresses permission and requests for permission

May I go to the bathroom? (I am asking for permission to go to the bathroom.)
You may go to the bathroom. (You have permission to go to the bathroom.)

Might

The modal verb might primarily expresses possibility, suggestions, commands, and requests. For example:

  • The baby might fall asleep early. (possibility)
  • You might want to try a different pair of pants. (suggestions)
  • You might keep that opinion to yourself next time. (command)
  • Might we go hiking next weekend? (request)

More specifically:

  1. Expresses possibility

She might apply for graduate school once she finishes college. (It is possible that she will apply for graduate school once she finishes college.)

  1. Expresses suggestions

You might wash your hands before you eat dinner. (It is suggested that you wash your hands before you eat dinner.)

  1. Expresses commands

You might watch your tone with me. (It is commended that you watch your tone with me.)

Must

The modal verb must primarily expresses obligation, necessity, commands, and deductions. For example:

  • She must finish her vegetables first. (obligation)
  • You must take the class Introduction to Graduate Studies. (necessity)
  • Students must stay out of the Dark Forest. (command)
  • That must be Espen on the phone. (deduction)

More specifically:

  1. Expresses obligation

You must attend the recital. (You are obligated to attend the recital.)

  1. Expresses necessity

You must buy a ticket to board the train. (It is necessary for you to buy a ticket to board the train.)

  1. Expresses commands including prohibitions, demands, suggestions, and permissions

You must not steal. (You are prohibited from stealing.)
You must bring your apple pie. (You are demanded to bring your apple pie.)
You must try the cranberry cookies. (It is suggested that you try the cranberry cookies.)
You must not borrow my car tomorrow. (You do not have permission to borrow my car tomorrow.)

  1. Expresses deductions of certainty

A lack of butter must be the problem. (It is deduced that a lack of butter is the problem.)

Shall

The modal verb shall primarily expresses futurity, suggestions, offers, and commands. For example:

  • We shall take the train to the city. (futurity)
  • Shall you paint your living room blue? (suggestions)
  • Shall I finish the laundry for you? (offer)
  • Employees shall not drink during working hours. (command)

More specifically:

  1. Expresses futurity including decisions, predictions, intentions, and promises

We shall travel to Rome next year. (We decided to travel to Rome next year.)
This winter shall be snowier than usual. (I predict that this winter is snowier than usual.)

  1. Expresses suggestions and offers

Shall we try a new restaurant? (I suggest that we try a new restaurant.)

  1. Expresses commands including obligation, prohibitions, and threats

Members shall not mingle with non-members on the golf course. (Members are prohibited from mingling with non-members on the golf course.)
I shall see your head on a stake. (I am threatening to put your head on a stake.)

Should

The modal verb should primarily expresses suggestions, necessity, obligation, and deductions. For example:

  • You should leave the cuffs on that blouse. (suggestion)
  • Employees should stay home when ill. (necessity)
  • You should love your children. (obligation)
  • We should need only a few more hours. (deduction)

More specifically:

  1. Expresses advisability including suggestions and recommendations

You should take the first exit, not the second. (It is suggested that you take the first exit, not the second.)

  1. Expresses necessity and, to a lesser extent, obligation

You should avoid pesto if you are allergic to nuts. (It is necessary for you to avoid pesto if you are allergic to nuts.)
You should bring a gift to the reception. (You are obligated to bring a gift to the reception.)

  1. Expresses predictions and deductions

Poppy should be walking by now. (It is deduced that Poppy is walking now.)
The train should be here shortly. (It is predicted that the train will arrive shortly.)

  1. Expresses conditionality and contingency

Should Grandpa arrive early, my brother will pick him up. (Grandpa arriving early is the condition necessary for my brother picking him up.)

Will

The modal verb will primarily expresses futurity, commands, suggestions, offers, and requests. For example:

  • A nurse will call you this afternoon. (futurity)
  • You will wash the dishes right now. (command)
  • You will want to see the bay if you visit Mobile. (suggestion)
  • My husband will help you put up your Christmas lights. (offer)
  • Will you please pass the salt? (request)

More specifically:

  1. Expresses futurity including decisions, predictions, intentions, and promises

My flight will leave for Europe in the morning. (My flight leaves for Europe in the morning.)
Next summer will be dry. (It is predicted for next summer to be dry.)

  1. Expresses commands

You will take off your shoes when you enter my house. (It is commanded that you take off your shoes when you enter my house.)

  1. Expresses suggestions

He will want to bring some extra cash. (It is suggested that he bring some extra cash.)

  1. Expresses offers

She will mail the package for you. (It is offered for her to mail the package for you.)

  1. Expresses requests

Will you please shut up? (It is requested that you please shut up.)

Would

The modal verb would primarily expresses contingency, futurity, habituality, desires, preferences, suggestions, offers, commands, and requests. For example:

  • I would help if you asked. (contingency)
  • She said she would come tonight. (futurity)
  • My brother would read that book every night before bed. (habituality)
  • I would like some milk please. (desire)
  • Would you prefer coffee or tea? (preference)
  • You would want to avoid the main highway this time of day. (suggestion)
  • She would take your Sunday shift. (offer)
  • Would you shut up! (command)
  • Would you lend me a baking dish? (request)

More specifically:

  1. Expresses conditionality and contingency

If you were me, then you would understand. (Your being me is the condition necessary for you understanding.)

  1. Expresses futurity including decisions, predictions, intentions, and promises within past tense constructions

You said you would come to my party. (You said, “I will come to your party.”)

  1. Expresses desires and preferences

My daughter would love more Elmo toys. (My daughter desires more Elmo toys.)

  1. Expresses suggestions

He would want to wash the fruit first. (It is suggested that he wash the fruit first.)

  1. Expresses offers

I would take the table off your hands. (I am offering to take the table off your hands.)

  1. Express requests and commands

Would you bring some of your famous pickles? (It is requested that you bring some of your famous pickles.)

  1. Expresses habituality, specifically past habituality

She would always nurse to sleep at night. (She used to always nurse to sleep at night.)

Modal verbs are a type of auxiliary verb that express modality in the English language. The nine English modals — can, could, may, might, must, shall, should, will, and would — each have multiple meanings depending on use and context. Both native English speakers and English language learners must learn the grammar, which includes the lack of conjugated forms and the position in verb phrases, of modal verbs in order to fully use and understand verbs the English language.

See also English Quasi-modal Verbs for information on the subset of modal verbs that possess some but not all grammatical properties of prototypical modals.

Summary

Modal verbs are a type of auxiliary verb that express modality — the grammaticalized expression of the subjective attitude of the speaker, which includes opinions about possibility, probability, necessity, obligation, permissibility, ability, desire, and contingency — in the English language. Modal verbs are a distinct set of verbs unique to Germanic languages and to Modern English especially that differ from prototypical verbs in form and function.

The nine full modal verbs in the English language are can, could, may, might, must, shall, should, will, and would.

Modal verbs are neutral and defective. The neutralization of modal verbs refers to the lack of a separate third person singular simple present tense form. The defectiveness of modal verbs refers to the lack of non-tensed forms.

Modal verbs appear before the head of the main verb functioning as the predicate and always appears at the beginning of the verb phrase in the initial position.

The semantic and pragmatic meanings of modal verbs are numerous and nuanced.

References

Bybee, Joan, Revere Perkins, and William Pagliuca. 1994. Mood and modality. The evolution of grammar: Tense, aspect, and modality in the languages of the world, 176-242. Chicago: The University of Chicago Press.
Huddleston, Rodney. 1984. Introduction to the grammar of English. Cambridge: Cambridge University Press.
Oxford English Dictionary.
Palmer, F. R. 1990. Modality and the English modals. London: Longman.

More in English Verbs

  • Grammatical Aspect

    Grammatical aspect is the grammaticalized expression of the temporal structure of an action or state. Temporal structure roughly relates to duration....

    Heather JohnsonJune 20, 2018
  • ESL Recipe Lesson Plan: Practice the Imperative Mood

    Many English language learners hope to function fully and completely in the English language. Learning to follow and write recipes is...

    Heather JohnsonFebruary 25, 2018
  • English Auxiliary Verbs

    Auxiliary verbs are a subcategory of English verbs that provide additional semantic or syntactic information about the main verb in the...

    Heather JohnsonMarch 1, 2016
  • Ambitransitive English Verbs

    Verbs are traditionally defined as “words that describe actions or states of being.” Main or principal English verbs may be either...

    Heather JohnsonFebruary 25, 2016
  • Attributive Ditransitive English Verbs

    Traditional notional grammars define verbs as “action or state of being words.” Transitive verbs in English grammar are main verbs that...

    Heather JohnsonFebruary 23, 2016