Auxiliary Verb

Recognize an auxiliary verb when you see one. Every sentence must have a verb. To depict doable activities, writers use action verbs. To describe conditions, writers choose linking verbs. Sometimes an action or condition occurs just once—bang!—and it's over.

Nate stubbed his toe.

He is miserable with pain.

Other times, the activity or condition continues over a long stretch of time, happens predictably, or occurs in relationship to other events. In these instances, a single-word verb like stubbed or is cannot accurately describe what happened, so writers use multipart verb phrases to communicate what they mean. As many as four words can comprise a verb phrase.

A main or base verb indicates the type of action or condition, and auxiliary—or helping—verbs convey the other nuances that writers want to express. Read these three examples:

Sherylee smacked her lips as raspberry jelly dripped from the donut onto her white shirt.

Sherylee is always dripping something.

Since Sherylee is such a klutz, she should have been eating a cake donut, which would not have stained her shirt.

In the first sentence, smacked and dripped, single-word verbs, describe the quick actions of both Sherylee and the raspberry jelly.

Since Sherylee has a pattern of messiness, is dripping communicates the frequency of her clumsiness. The auxiliary verbs that comprise should have been eating and would have stained express not only time relationships but also evaluation of Sherylee's actions.

Below are the auxiliary verbs. You can conjugate be, do, and have; the modal auxiliaries, however, never change form. 

Understand the dual nature of be, do, and have.

Be, do, and have are both stand-alone verbs and auxiliary verbs. When these verbs are auxiliary, you will find them teamed with other verbs to complete the verb phrase. Compare these sentences:

Freddy is envious of Beatrice’s steaming bowl of squid eyeball stew.

Is = linking verb.

Freddy is studying Beatrice’s steaming bowl of squid eyeball stew with envy in his eyes.

Is = auxiliary verb; studying = present participle completing the verb phrase.

We did our homework for Mrs. Long.

Did = action verb.

We’re not slackers! We did prepare our homework for Mrs. Long.

Did = auxiliary verb; prepare = main verb completing the verb phrase.

Selena has twelve orange goldfish in her aquarium.

Has = action verb.

Selena has bought a catfish to help keep the tank clean.

Has = auxiliary verb; bought = past participle completing the verb phrase.

Form progressive tenses with the auxiliary verb be.

All progressive tenses use a form of be. Present progressive follows this pattern:

AM, IS, OR ARE + PRESENT PARTICIPLE

Use the present progressive tense to convey an action or condition happening right now.

I am baking chocolate-broccoli muffins today.

Am = auxiliary verb; baking = present participle completing the verb phrase.

Past progressive follows this pattern:

WAS OR WERE + PRESENT PARTICIPLE

Use the past progressive tense to show either 1) an action or condition that continued in the past or 2) an action or condition interrupted by another.

Naomi was hoping for an A in her organic chemistry class.

Was = auxiliary verb; hoping = present participle completing the verb phrase.

Future progressive looks like this:

WILL + BE + PRESENT PARTICIPLE

Use the future progressive tense to indicate an action that will continue in the future.

I will be growing broccoli in the backyard this spring.

Will, be = auxiliary verbs; growing = present participle completing the verb phrase.

Form passive voice with be.

You can make any transitive verb—an action verb that can take a direct object—passive with the auxiliary verb be.

Active voice looks like this:

SUBJECT + VERB + DIRECT OBJET

Example:

Frank devoured a bacon double cheeseburger.

Passive voice makes these changes:

DIRECT OBJET AS SUBJECT + FORM OF BE + PAST PARTICIPLE + BY + SUBJECT AS OBJECT OF THE PREPOSITION

The double bacon cheeseburger was being devoured by Frank.

Form perfect tenses with have.

All perfect tenses use a form of have. Present perfect follows this pattern:

HAS OR HAVE + PAST PARTICIPLE

Use the present perfect tense to convey an action or condition that began in the past but continues [or is finished] in the present.

Marge has bought earplugs to drown out her husband's snoring.

Has = auxiliary verb; bought = past participle completing the verb phrase.

Past perfect follows this pattern:

HAD + PAST PARTICIPLE

Use the past perfect tense to show that one action in the past occurred before another.

Because Marge had purchased the earplugs, she no longer fantasized about smothering George with a pillow.

Had = auxiliary verb; purchased = past participle completing the verb phrase.

Future perfect follows this pattern:

WILL + HAVE + PAST PARTICIPLE

Use the future perfect tense to indicate that an action will be finished in the future.

This Sunday, Marge will have gotten an entire week of uninterrupted sleep.

Will, have = auxiliary verbs; gotten = past participle completing the verb phrase.

Form emphatic tenses with do.

When you use a form of do as an auxiliary verb, you form the emphatic tense. This tense is useful for asking questions or emphasizing an action. The patterns look like these:

FORM OF DO + MAIN VERB

FORM OF DO + SUBJECT + MAIN VERB… ?

I did not eat your leftover pizza!

Did = auxiliary verb; eat = main verb completing the verb phrase.

Do you always accuse the first person you see?

Do = auxiliary verb; accuse = main verb completing the verb phrase.

Doesn't the evidence point to Samuel, who still has a bit of black olive stuck to his front tooth?

Does = auxiliary verb; point = main verb completing the verb phrase.

Understand the job of modal auxiliary verbs.

Modal auxiliary verbs never change form. You cannot add an -ed, -ing, or -s ending to these words. Can, could, may, might, must, ought to, shall, should, will, and would have only one form.

You can use modal auxiliary verbs in these patterns:

MODAL + MAIN VERB

MODAL + BE + PRESENT PARTICIPLE

MODAL + HAVE + PAST PARTICIPLE

With modal auxiliaries, you can indicate necessity or obligation:

To lose her orange glow, Yvonne should eat fewer carrots.

John must remember his wife's birthday this year.

If Cecilia wants a nice lawn, she ought to be raking the leaves.

Or you can show possibility:

Fred might share his calculus homework if you offer him a slice of pizza.

Ann could have run the half marathon if she had started to train four months ago.

Modal auxiliaries also show willingness or ability:

Nicole will babysit your pet iguana for a reasonable fee.

Jason can pass chemistry this semester if he stops spending his study time at the arcade.