Auxiliary Verbs — Definition & Examples
What is an auxiliary verb?
Auxiliary verbs, also known as helping verbs, connect with the main verb in a sentence to add context and functionality. They cannot exist in a sentence as a standalone verb – they must combine with another type of verb, usually an action verb, to create a verb phrase.
Common examples of auxiliary verbs are forms of be, like am, is, and was.
Types of auxiliary verbs
The two main types of auxiliary verbs are primary and modal.
Primary auxiliary verbs express tense, grammatical mood, and voice through conjugation. In the following examples, the auxiliary verbs are in bold.
Tense: Specifies if the verb happens in the past, present, or future.
Past tense: He was working.
Present tense: He is working.
Future tense: He will be working.
Grammatical Mood: Indicates whether a verb conveys a fact (indicative mood), command (imperative mood), question (interrogative mood), or condition (conditional mood). Auxiliary verbs can take on a negative form (like aren’t and didn’t).
Indicative: The train is scheduled to leave at 5:00.
Imperative: Be quiet!
Interrogative: Are you going to the movies?
Conditional: If it was warm, I would be swimming.
Voice: Auxiliary verbs can pair with main verbs to create the passive voice. With passive voice, the action of the sentence happens to the subject rather than being completed by them.
Passive: The student was called to the front of the class.
Active: The teacher called the student to the front of the class.
Modal auxiliary verbs express ideas of necessity, ability, intention, and possibility. Modal verbs are not conjugated, meaning their verb form does not change.
Necessity: Action needs to occur
Jerry told us we should leave before the storm hits.
Ability: Action is capable of occurring
We could take a later flight.
Intention: Action intends to occur
Olivia will write the thank you cards tomorrow.
Possibility: Action might occur
We may be able to hold the meeting in the conference room.
Auxiliary verb examples
The following chart contains a list of all the primary auxiliary verbs along with a sentence using each:
| Primary Auxiliary Verb | Examples |
|---|---|
| • be
• am • are • being • is • was • were |
• Will you be driving to the wedding?
• I am thinking about moving. • We are planning a surprise party. • The cat was being chased by the dog. • Who is going to the lake this weekend? • Lucy was listening to a book on tape. • They were dancing all night. |
| • do
• did • does • doing |
• Do they open at 9:00 or 10:00?
• Carl didn't want to move to New York. • Why does Erin not have a cell phone? • What are you doing here? |
| • have
• had • has • having |
• They have to leave in the morning.
• Stephanie had finished all of her homework. • No one has lived here for years. • The kids were having fun at the party. |
The following chart contains a list of all of the modal auxiliary verbs along with a sentence using each:
| Modal Auxiliary Verbs | Examples |
|---|---|
| can | Do you think I can pass the test? |
| could | Could you come to my office for a minute? |
| may | You may leave if you finish your work early. |
| might | Kevin might bring his dog along. |
| must | Why must we stay so late? |
| shall | They shall not scare me. |
| should | Leslie should arrive before noon. |
| will | Frank will enjoy the roller coaster. |
| would | Why would you say that? |