What Is an Auxiliary Verb? Types and Uses Explained

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auxiliary verb example
    auxiliary verb example
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You may have heard auxiliary verbs referred to as helping verbs, but what is this type of verb, and what does it do in English? When we say it is "helping" a main verb, we mean it's helping to clarify it. Auxiliary verbs help to clarify whether an action occurs, when the action of the main verb takes place, who or what is responsible for that action, and whether we are making a statement or asking a question. Explore what auxiliary verbs are and how they are used in English.

What Is an Auxiliary Verb?

When it comes to auxiliary verbs, 23 auxiliary verbs stand out. The "Big Three" auxiliary verbs are "be," "have" and "do" in all their forms. But, there are also a few other auxiliary verbs called modal auxiliary verbs. Let’s look at both types of auxiliary verbs.


Auxiliary Verbs Be, Do, and Have

When it comes to auxiliary verbs, be, do, and have are your go to. These auxiliary verbs can be conjugated and include these forms:

  • be
  • being
  • been
  • am
  • is
  • are
  • was
  • were
  • have
  • has
  • had
  • do
  • does
  • did

Modal Auxiliary Verbs

Modal verbs are a special class of auxiliary verbs used to express conditionality, necessity, obligation, ability, and wishful desire. The modal verbs in English are:

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

These little guys have the ability to make big changes in a sentence, so it's important to know them and use them correctly. Check out how they make big changes in sentences.

  • We shall overcome.
  • You should be dancing.
  • I will always love you.
  • If I had a million dollars, I would buy you an exotic pet.
  • You may be right; I may be crazy, but it just may be a lunatic you're looking for.
  • She might be mine.
  • I can see clearly now the rain is gone.
  • If I could turn back time...
  • You must love me.

Progressive Tenses With Auxiliary Verbs

In present progressive sentences, the verb expresses action in progress as the speaker says it. "I am typing" is an example of present progressive. In it, the main verb is "type" while the auxiliary verb "be" is conjugated according to the subject, "I." Let’s look at a few more examples of present progressive tense.

  • Daniel is playing.
  • The towels are drying.
  • Alexis is waiting.

Past and Future Progressive Tense

We also use past and future progressives to explain what was or will be happening when some other event occurred or will occur.

  • He was watching TV when the phone rang.

Here, "was" is the auxiliary that helps us understand when the main verb (watch) happened.

  • We will be driving to Virginia during your party.

The future progressive actually uses two auxiliary verbs (will and be) to tell us that this action (drive) takes place in the future.


Form Passive Voice With Auxiliary Verbs

Active sentences are more exciting. Active sentences use the formula:

Subject + verb + direct object.

However, any sentence can be made passive by adding a form of be. A passive sentence looks like:

Object + be form + part participle + by (preposition) + subject.

Here are some examples of passive voice:

  • The chair was moved to the other side of the room.
  • I was hit in the head and knocked unconscious.
  • It has been decided that the play will be canceled

Notice you could easily add "by a purple monster" to the end of your verb phrase and still have a grammatically correct sentence.

  • The chair was moved (by a purple monster) to the other side of the room.
  • I was hit in the head (by a purple monster) and knocked unconscious (by a purple monster).
  • It has been decided (by a purple monster) that the play will be canceled (by a purple monster)

There's nothing grammatically wrong with passive voice; it's an excellent use of the verb "be." It's just not very exciting writing. It's more interesting to say:

  • A purple monster moved the chair across the room.
  • A purple monster hit me in the head and knocked me out.
  • A purple monster has decided to cancel the play. Take it up with him.

Perfect Tenses With Auxiliary Verbs

The perfect tenses in English explain the order of things:

  • present perfect - explains what has happened up until now
  • past perfect - explains what had happened in the past before something else happened in the past
  • future perfect - tells us what will have happened up to a certain point in the future

All the perfect tenses use at least one auxiliary verb, "have."

  • I have visited Stockholm many times.
  • He had seen many cathedrals, but none so grand as that one.

The future perfect also uses "will."

  • We will have traveled to every country in the world after this trip.

And the progressive perfect tenses also use "be."

  • She has been living in Sweden for 10 years.
  • He had been touring Europe for 3 months.
  • We will have been flying for 31 hours by the time we get home.

Auxiliary Verbs for Questions

In many languages, changing a statement to a question is as easy as changing your inflection or punctuation. In Spanish, for example, you can say, "Ella habla Inglés," or you can ask, "¿Ella habla Inglés?" The word order does not change. In English, however, the statement is, "She speaks English," whereas the question changes to, "Does she speak English?" English questions almost always use an auxiliary verb.

Dummy Verbs and Tag Questions

A dummy verb is a verb we use in place of a main verb. Usually we use dummy verbs when we've already used the main verb once or twice, and we don't want to repeat it. For example, if someone asks you, "Do you know the muffin man?" you don't want to respond, "Yes, I know the muffin man." It's too long and unnecessary a response when you can simply say, "Yes I do." In this case, "do" is the dummy verb replacing the main verb "know."

Or perhaps your wife tells her friend, "My husband wants to help you move your heavy furniture." You can respond with a simple "Do I?"

We also use auxiliary verbs in tag questions, which are short questions added to the end of a statement. If the statement is negative, the tag question is affirmative, and vice versa.

  • Sheila has been to Japan twice, hasn't she?
  • You're writing a book, aren't you?
  • He can't speak Mandarin, can he?
  • Bob doesn't bake a lot, does he?
  • Bob bakes a lot, doesn't he?

The auxiliary verbs used in the tag questions are the same as those used in the statement with one exception. In the last sentence, the statement doesn't have an auxiliary verb, so the dummy verb "does" is used in the tag question.

Auxiliary Verbs in Action

Auxiliary verbs have different uses in English. Auxiliary verbs are helpful in writing. With your verb knowledge on fire, check out some action verb examples.