What Is a Verb? | Definition, Examples & Types

A verb is a part of speech used to describe an action carried out by the subject of the sentence. This could be anything from a deliberate physical or mental action to a natural process or passive state of being, and the subject could be a person, animal, thing, or even abstract concept.

A grammatically complete sentence must contain at least one verb (though you will often encounter sentences without one in less formal contexts). In fact, a sentence can consist entirely of one verb (e.g., “Sit”). But outside of imperative sentences like this, the verb is normally preceded by a subject (e.g., “The dog sits”).

Use QuillBot’s free Grammar Checker to make sure you’re using verbs correctly in all your writing.

Verb conjugation

Verb conjugation is the way in which verbs change their forms depending on how they are being used. The basic form of a verb (e.g., “go,” “be,” “run”) is called the infinitive, but in most cases the verb is conjugated in some other way. Verbs are conjugated based on:

• Subject
• Tense
• Mood
• Voice

Subject-verb agreement

A verb must agree with its subject—the noun, pronoun, or noun phrase that represents the person or thing performing the action and which typically appears right before the verb.

In English, subject-verb agreement usually just involves making sure the verb matches the subject in number: singular or plural. The singular form ends in “s,” while the plural does not. However, note that the first-person pronoun “I” uses the usual plural form instead of the singular.

This singular vs. plural distinction only applies in the present tense; other tenses use the same form for singular and plural (e.g., “he ran,” “they ran”).

An exception is the highly irregular verb “be.” In the present tense, the unique form “am” (not “is”) is used for the first-person singular. And there are different forms of the past tense, unlike with other verbs.

Verb tenses and aspects

Tense indicates when something happened, is happening, or will happen:

• The past tense means something has already happened
• The present tense means it’s happening now
• The future tense means it hasn’t happened yet

Each of these tenses has four aspects: simple, progressive, perfect, and perfect progressive that express different meanings.

All tenses except the simple past and simple present are formed with multiple verbs in different combinations—including the auxiliary verbs “be,” “have,” or “will,” a present participle (“-ing” form), or a past participle (“-ed” form).

The table shows examples of all tenses and aspects of the regular verb “wait” in the first-person singular.

Verb moods

A verb’s mood is used to express the tone and purpose of a sentence—is it a question? A command? A statement? The four main grammatical moods used in English are explained in the table.

Active vs passive voice

A sentence can be written in two different voices:

• In the active voice, the subject performs the action of the verb (e.g., “Cooper ate the food”).
• In the passive voice, the subject is the person or thing being acted upon (e.g., “The food was eaten”).

The passive voice is formed using a form of the verb “be” and the past participle of the main verb. The person or thing performing the action can still be specified with the preposition “by” (e.g., “The food was eaten by Cooper”), although this is more long-winded than an active phrasing.

If it’s important to know who or what performed the action, it’s best to use the active voice. If who or what did it is irrelevant or unknown, or if you want to place greater emphasis on the person or thing being acted upon, then the passive voice is a good choice.

Irregular verbs

A regular verb is any verb that follows the standard conjugation rules, forming its simple past and past participle with the standard “-ed” suffix. The simple past and past participle of a regular verb are always identical to each other.

An irregular verb instead forms its simple past and past participle in some other way, such as by changing the vowel in the middle of the verb (e.g., “swam”) or by adding a different suffix (e.g., “broken”). Additionally, the simple past and past participle of an irregular verb are sometimes (not always) different from each other.

Most verbs in English are regular, but many of its irregular verbs occur extremely often (e.g., the auxiliary verbs “be,” “have,” and “do”). Check a dictionary if you’re unsure; it should list the past tenses of any irregular verbs.

Transitive and intransitive verbs

Verbs are classed as intransitive, transitive, or ditransitive:

• An intransitive verb has no direct object since it describes an action that isn’t done to a specific object.
• A transitive verb is followed by a direct object that represents the thing or person being acted upon.
• A ditransitive verb is followed by two objects: an indirect object representing the person or thing receiving the effects of the action, and then a direct object.

Some verbs can only function as one of these types, but many can function differently depending on the specific sense in which they are used, as seen with “read” in the table below.

What is a linking verb?

A linking verb (aka copular verb) is used to connect the subject with some word or phrase (such as a pronoun or adjective) that describes or identifies it. This word or phrase is called a subject complement; it acts as something like a second subject rather than an object.

Most linking verbs may also be used in other ways, indicating a specific action rather than describing the subject (e.g., “Harold looked at the sky”).

What is an auxiliary verb?

An auxiliary verb is used in combination with another verb to modify its meaning, indicating mood, voice, and tense, as well as in negative statements (in combination with adverbs like “not” and “never”) and questions. The main auxiliary verbs are be, have, and do.

The verb modified by an auxiliary verb is called the main verb. The auxiliary verb is conjugated, whereas the main verb appears as an infinitive (e.g., “look”) or participle (e.g., “looked,” “looking”). Sometimes, several auxiliary verbs appear consecutively.

What is a modal verb?

A modal verb is a special kind of auxiliary that’s used to express ability, possibility, obligation, necessity, or permission. Unlike the other auxiliary verbs, modal verbs are not conjugated—they have one fixed form.

The main English modal verbs are:

• May
• Might
• Can
• Could
• Shall
• Should
• Will
• Would
• Ought to

Stative and dynamic verbs

Verbs can also be classified as stative or dynamic:

• A dynamic verb (aka action verb) describes a specific, temporary action (e.g., “run,” “drive,” “generate”). It may be used in the progressive aspect to indicate an ongoing action (e.g., “is running”).
• A stative verb describes a (mental, physical, or emotional) state of being or perception (e.g., “be,” “possess,” “know”).

Because they describe a general state rather than an action, it usually doesn’t make sense to use stative verbs in the progressive aspect:

Phrasal verbs