Verbs: Be, Auxiliaries, and Modals

Verbs: Be, Auxiliaries, and Modals

The Eight Forms of Be

The verb be has eight forms, with am and are as present tense forms along with is, and both was and were as past tense forms.

Base	Present Tense Forms	-ing	Past	Past Participle
be	am, are, is	being	was, were	been

An independent clause needs a complete verb. Verb forms such as the -ing form and the past participle are not complete because they do not show tense. They need auxiliary verbs to complete their meaning as a verb of a clause. A complete verb includes a verb form preceded by any necessary auxiliary verb or modal auxiliary verb.

Auxiliary Verbs
do: does, do, did
be: be, am, is, are, was, were, being, been
have: has, have, had

Modal Auxiliary Verbs
will, would
can, could
shall, should
may, might, must

Auxiliary verbs and modal auxiliary verbs can be used in combination. Whatever the combination, the verb form immediately following the final auxiliary or modal verb is fixed: base form, -ing, or past participle. Try the following tips to decide which form to use.

Combining Auxiliary, Modal Auxiliary and Verb Forms

1.	After do, does, did, will, would, can, could, shall, should, may, might, and must, use the base form. He might stay. They must have dinner soon. Did she leave?
2.	After has, have, and had, use the past participle. It has snowed. They should have gone (not "They should have went"). They had eaten when I arrived. In informal speech, we run sounds together, and the pronunciation may be mistakenly carried over into writing. She should have left that job last year. The pronunciation of the contraction should've is probably responsible for the nonstandard form should of. Edit carefully for the appearance of the word of in place of have in verb phrases.
3.	After be, am, is, are, was, were, and been, use the -ing form for active voice verbs. She is taking her driving test. You were watching. He might have been driving. They could be jogging. To form a complete verb, always use a be auxiliary before the -ing form. The -ing form alone can never be a complete verb in a clause.
4.	After be, am, is are, was, were, been, and being, use the past participle for passive voice. They were taken to a tropical island for their anniversary. The faucet should be fixed. The cake might have been eaten. The house is being decorated.

Note:

Be requires a modal before it to form a complete verb (could be jogging; will be closed). Been requires have, has, or had (have been driving; has been eaten). Being must be preceded by am, is, are, was, or were to form a complete verb.