Verbs
The verb of a sentence usually expresses action (jump, think) or being (is, become). It is composed of a main verb possibly preceded by one or more helping verbs.
Notice that words can intervene between the helping and the main verb (was not completed).
Main verbs
The main verb of a sentence is always the kind of word that would change form if put into these test sentences:
BASE FORM
Usually I walk.
Usually I ride.
PAST TENSE
Yesterday I walked.
Yesterday I rode.
PAST PARTICIPLE
I have walked many times before.
I have ridden many times before.
PRESENT PARTICIPLE
I am walking right now.
I am riding right now.
-S FORM
Usually he/she/it walks.
Usually he/she/it rides.
If a word doesn’t change form when slipped into these test sentences, you can be certain that it is not a main verb.
When both the past-tense and the past-participle forms of a verb end in -ed, the verb is regular (walked, walked). Otherwise, the verb is irregular (rode, ridden).
The verb be is highly irregular, having eight forms instead of the usual five: the base form be; the present-tense forms am, is, and are; the past-tense forms was and were; the present participle being; and the past participle been.
Basic verb forms
NOTE:Some verbs are followed by words that look like prepositions but are so closely associated with the verb that they are a part of its meaning. These words are known as particles. Common verb-particle combinations include bring up, call off, drop off, give in, look up, run into, and take off.
A lot of parents pack up their troubles and send them off to camp.
—Raymond Duncan
Helping verbs
There are twenty-three helping verbs in English: forms of have, do, and be, which may also function as main verbs; and nine modals, which function only as helping verbs. The forms of have, do, and be change form to indicate tense; the nine modals do not.
FORMS OF HAVE, DO, AND BE
have, has, had, do, does, did, be, am, is, are, was, were, being, been
MODALS
can, could, may, might, must, shall, should, will, would
The verb phrase ought to is often classified as a modal as well.
Exercise: Parts of speech: verbs 1
Exercise: Parts of speech: verbs 2
Exercise: All parts of speech 1
Exercise: All parts of speech 2
Related topics:
Linking verbs
Active verbs
Subject-verb agreement
Standard English verb forms
Verb tense and mood
Multilingual and ESL challenges with verbs
base form The dictionary form of a word, without any prefixes or suffixes or markers of tense or case.
past participle A verb form usually ending in -d, -ed, -n, -en, or -t and functioning as part of a main verb or as an adjective: walked, broken, seen.
present participle A verb form ending in -ing and functioning as part of main verbs or as an adjective.
preposition A word placed before a noun or noun equivalent to form a phrase modifying another word in the sentence: They fell in line with the crowd.
particle A word that looks like a preposition but that is so closely associated with a verb that it is part of the meaning of the verb: look up, give in.