3 Things to Know About Verb Phrase Structure

1) The verb element in a sentence comprises of one or more words that make up the verb phrase. For example:

I SAW a cat. 

I HAVEN'T SEEN anything. 

DID I SEE that? 

I SHOULDN'T HAVE BEEN SEEING her.

2) The verb phrase consists of at least one main verb and can have up to four auxiliary verbs. For example:

a) kiss.

b) is kissing.

c) has been kissing.

d) must have been kissing.

e) must have been being kissed. (This is rare).

3) Three types of verb can occur with the verb phrase.

a) Full - Or lexical - These have a clearly statable meaning and act as main verbs:

run, jump, go, look, want, think, find.

b) Modal auxiliary - These express a range of judgments about the events and can only be used as auxiliary verbs:

will, shall, may, might, can, could.

c) Primary - These can be either main or auxiliary verbs and there are three of them - BE, HAVE, DO. For example:

Main use: 

They ARE happy. 

She HAS a dog. 

They DO sums.

Auxiliary use:

They ARE going.

She HAS seen it.

DO they go?

There are certain other verbs that do not fall clearly into these types.