What Are Auxiliary (or Helping) Verbs in English Grammar?

Glossary of Grammatical and Rhetorical Terms

auxiliary verb
Common auxiliaries (or helping verbs) in English include be (am, are, is, was, were), have, do, may, might, must, can, and should. (lvcandy/Getty Images)

In English grammar, an auxiliary is a verb that determines the mood, tense, voice, or aspect of another verb in a verb phrase. Auxiliary verbs include be, do, and have along with modals such as can, might, and will. Contrast with main verb and lexical verb.

Auxiliaries are also called helping verbs because they help to complete the meaning of main verbs. Unlike a main verb, an auxiliary can't be the only verb in a sentence (except in elliptical expressions where the main verb is understood as if it were present).


Auxiliary verbs always precede main verbs within a verb phrase, as in the sentence "You will help me." In interrogative sentences, the auxiliary appears in front of the subject, as in "Will you help me?" 


From the Latin, "help"

Examples and Observations

  • "Dinner is finished and the dishes are in the dishwashing machine."
    (John Cheever, "The Country Husband," 1955)
    [In this sentence, note that there are two forms of the verb be: (1) is functions as an auxiliary and are functions as a main verb.] 
  • "Mrs. Slump was standing in the door with her back toward us when we drove up."
    (Grace Stone Coates, "Wild Plums," 1929)

  • "If I have seen further, it is by standing on the shoulders of giants."
    (Isaac Newton)
  • "A wise man will make more opportunities than he finds."
    (Sir Francis Bacon)
  • "I did not invent Irish dancing."
    (Bart Simpson, The Simpsons)
  • "In the beginning the Universe was created. This has made a lot of people very angry and been widely regarded as a bad move."
    (Douglas Adams, The Restaurant at the End of the Universe. Pan Books, 1980)
  • "I thought for a minute that something awful might have happened"
    (Maya Angelou, I Know Why the Caged Bird Sings. Random House, 1969)
  • "And as for Gussie Fink-Nottle, many an experienced undertaker would have been deceived by his appearance and started embalming him on sight."
    (P.G. Wodehouse, Right Ho, Jeeves, 1934)
  • "Fern couldn't eat until her pig had had a drink of milk."
    (E.B. White, Charlotte's Web. Harper, 1952)
    [In this sentence, note that (1) the negative n't is attached to the first auxiliary, could; and (2) in the phrase had had, the first had functions as an auxiliary and the second had functions as a main verb.] 
  • The Auxiliary Verbs in English
    "The auxiliary verbs of English are the following:
    1. can, may, will, shall, must, ought, need, dare [modals]
    2. be, have, do, use [non-modals]
    Some of them appear in idioms--be going, have got, had better/best, would rather/sooner (as in It is going to rain, I've got a headache, etc.)--and in such cases it is just the first verb (be, have, had, would) that is an auxiliary, not the whole idiom."
    (R. Huddleston and G. Pullum, The Cambridge Grammar of the English Language. Cambridge University Press, 2002)
  • Differences Between Auxiliary Verbs and Main Verbs
    "The auxiliary verbs differ from main verbs in the following ways:
    1. They do not take word endings to form participles or agree with their subject. Thus, we say She may go to the store, but never She mays go to the store.
    2. They come before not in negative clauses, and they do not use do to form the negative: You might not like that. A main verb uses do to form the negative and follows not: You do not like that.
    3. They come before the subject in a question: Can I have another apple? Would you like to go to the movies? Main verbs must use do and follow the subject to form questions: Do you want to go to the movies?
    4. They take the infinitive without to: I will call you tomorrow. A main verb that takes an infinitive always uses to: I promise to call you tomorrow."
    (The American Heritage Guide to Contemporary Usage and Style. Houghton Mifflin, 2005)
  • The Maximum Number of Auxiliaries
    "English allows up to three auxiliaries in a sentence, four in a passive . . .. The first must be finite and the others nonfinite. In the following example, we have a modal followed by have followed by the past participle of the verb 'to be':
    I could've been a contender.
    (Marlon Brando, On the Waterfront)"
    (Barry J. Blake, All About Language. Oxford University Press, 2008)
  • Irregular Auxiliaries
    "The verbs be, have, do, and go are irregular in many of the world's languages. They are the most commonly used verbs in most languages and often pitch in as auxiliaries: 'helper' verbs that are drained of their own meanings so that they may combine with other verbs to express tense and other grammatical information, as in He is jogging, He has jogged, He is going to jog. Many language scientists believe that the meanings of these verbs—existence, possession, action, motion—are at the core of the meanings of all verbs, if only metaphorically."
    (Steven Pinker, Words and Rules. HarperCollins, 1999)
  • Omitting Words After Auxiliary Verbs
    "To avoid repeating words from a previous clause or sentence we use an auxiliary verb (be, have, can, will, would, etc.) instead of a whole verb group (e.g. 'has finished') or instead of a verb and what follows it (e.g. 'like to go to Paris'):
    - She says she's finished, but I don't think she has. (instead of . . . has finished.)
    - 'Would any of you like to go to Paris?' 'I would.' (instead of I would like to go to Paris.)
    If there is more than one auxiliary verb in the previous clause or sentence, we leave out all the auxiliary verbs except the first instead of repeating the main verb. Alternatively, we can use two (or more) auxiliary verbs:
    - Alex hadn't been invited to the meal, although his wife had. (or . . . had been.)
    - 'They could have been delayed by the snow.' "Yes, they could.' (or . . . could have (been).)"
    (Martin Hewings, Advanced Grammar in Use, 2nd ed. Cambridge University. Press, 2005)

Pronunciation: og-ZIL-ya-ree vurb