Modal Verb

Definition of Modal Verb

A modal verb is a type of verb that joins up with another verb to create a mood or situation. Also known as a “modal auxiliary verb,” a modal verb expresses uncertainty, necessity, permission, or ability. Unlike auxiliary verbs, a modal verb never changes its form; therefore, it does not use “‑ing,” “‑en,” “‑s,” or infinitive forms. There are ten basic modal verbs:

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

However, as these verbs show, a modal verb does not have its own meaning; it must be accompanied by a base verb, such as “play,” “eat,” “drink,” “think,” etc. On the other hand, a modal verb never joins up with auxiliary verbs, like “do,” “does,” and “did.”

The negative form of a modal verb can be made by simply adding “not” to the verb. When in an interrogative form, a modal verb comes just before the subject of the sentence. For instance, in the sentence, “She thought, I must hurry before the robbers come” (The Interior Castle, by Jean Stafford), the word “must” is a modal verb. In its negative form, “not” will be added after “must,” and in its interrogative form, the modal verb will come just before the subject that it precedes in the affirmative sentence.

Characteristics of a Modal Verb


A modal verb is used when it is a certainty that something has happened, is happening, or will happen:

“It is snowing, so you must be feeling cold.”


“Can” and “could” are used when talking about an ability or skill, when making a request, or when asking for permission:

“He can speak many languages.”

Could I ask you a question?”


The modal verbs “can,” “could,” “may,” or “might” are used when granting permission in the present or future. “May” and “might” are also used when discussing uncertainties about past events:

“You may use my car tonight.”

“We may go shopping tonight, but I am not sure yet.”

“The fact that she failed the test surprised me. I heard she might have been suffering from a fever during the exam.”


The modal verb “would” is often used to discuss something that someone does now, or used to do in the past:

“When she lived in the U.S., she would often drink coffee in a café next to her apartment.”

Advice or Obligation

The modal verbs “must” and “should” are used when someone is offering advice or is discussing the importance (or unimportance) of something:

“The kids must finish their homework before they go to sleep.”

“You should be present for your final exam.”

Making Offers/Suggestions

The modal verb “shall” typically appears in the first-person narrative:

Shall I buy you an ice cream?” (Offer)

Shall we play cricket today?” (Suggestion)

Examples of Modal Verbs in Literature

Example #1: The Picture of Dorian Gray (by Oscar Wilde)

“There are many things that we would throw away if we were not afraid that others might pick them up.”

In this line, the author has used the modal verb “might” to show uncertainty about the past.

Example #2: The Things They Carried (by Tim O’Brien)

“Afterward, when the firing ended, they would blink and peek up. They would touch their bodies, feeling shame, then quickly hiding it. They would force themselves to stand. As if in slow motion, frame by frame, the world would take on the old logic –absolute silence, then the wind, then sunlight, then voices.”

Throughout this excerpt, O’Brien has used the modal verb “would” to discuss the past habits of a particular group of people.

Example #3: Emma (by Jane Austen)

“You might not see one in a hundred, with gentleman so plainly written as in Mr. Knightley … He will be a completely gross, vulgar farmer … “

In this extract, the author has used two modal verbs: “might” and “will.” “Might” indicates uncertainty about the future, while “will” shows the absolute certainty.

Example #4: The Gettysburg Address (by Abraham Lincoln)

“Government of the people, by the people, for the people, shall not perish from the earth.”

Lincoln has skillfully used the modal verb “shall” in his speech. Here, “shall” has several different functions; it poses as a suggestion, a possibility, and an offering of advice.


Modal verbs perform various functions, depending on how they are used within a given text. They show possibilities, abilities, and predictions. They aid writers in discussing the future with certainty, or discussing the past with uncertainty. They help writers make promises and decisions, as well as give permission or reassurance. Modal verbs also aid other verbs in expressing their meanings. Grammatically, modal verbs make sentences more complete and meaningful.