What is a verb?

A verb is often defined as a word which shows action or state of being. The verb is the heart of a sentence - every sentence must have a verb. Recognizing the verb is often the most important step in understanding the meaning of a sentence. In the sentence The dog bit the man, bit is the verb and the word which shows the action of the sentence.  In the sentence The man is sitting on a chair, even though the action doesn't show much activity, sitting is the verb of the sentence.  In the sentence She is a smart girl, there is no action but a state of being expressed by the verb is. The word be is different from other verbs in many ways but can still be thought of as a verb.

Unlike most of the other parts of speech, verbs change their form.  Sometimes endings are added (learn - learned) and sometimes the word itself becomes different (teach-taught).  The different forms of verbs show different meanings related to such things as tense (past, present, future), person (first person, second person, third person), number (singular, plural) and voice (active, passive). Verbs are also often accompanied by verb-like words called modals (may, could, should, etc.) and auxiliaries(do, have, will, etc.)  to give them different meanings.

One of the most important things about verbs is their relationship to time.  Verbs tell if something has already happened, if it will happen later, or if it is happening now.  For things happening now, we use the present tense of a verb; for something that has already happened, we use the past tense; and for something that will happen later, we use the future tense.  Some examples of verbs  in each tense are in the chart below:
 

Present	Past	Future
look	looked	will look
move	moved	will move
talk	talked	will talk

Verbs like those in the chart above that form the past tense by adding -d or -ed are called regular verbs.  Some of the most common verbs are not regular and the different forms of the verb must be learned.  Some examples of such irregular verbs are in the chart below:
 

Present	Past	Future
see	saw	will see
hear	heard	will hear
speak	spoke	will speak

The charts above show the simple tenses of the verbs.  There are also progressive or continuous forms which show that the action takes place over a period of time, and perfect forms which show completion of the action.  These forms will be discussed more in other lessons, but a few examples are given in the chart below:
 

Present Continuous	Present Perfect
is looking	has looked
is speaking	has spoken
is talking	has talked

Simple present tense verbs have a special form for the third person singular. Singular means "one" and plural means "more than one."  Person is used here to show who or what does the action and can have the following forms:
    1st person or the self (I, we)
    2nd person or the person spoken to (you)
    3rd person or a person not present (he, she, it, they)
The third person singular forms are represented by the pronouns he, she, it.  The chart below shows how the third person singular verb form changes:
 

Singular		Plural
1st Person (I)	see hear come	1st Person (we)	see hear come
2nd Person (you)	see hear come	2nd Person (you)	see hear come
3rd Person (he, she, it)	sees hears comes	3rd Person (they)	see hear come

A verb must "agree" with its subject. Subject-verb agreement generally means that  the third person singular verb form must be used with a third person subject in the simple present tense. The  word be - the most irregular and also most common verb in English - has different forms for each person and even for the simple past tense.  The forms of the word be are given in the chart below:
 

Number	Person	Present	Past	Future
Singular	1st (I)	am	was	will be
	2nd (you)	are	were	will be
	3rd (he, she, it)	is	was	will be
Plural	1st (we)	are	were	will be
	2nd (you)	are	were	will be
	3rd (they)	are	were	will be

Usually a subject comes before a verb and an object may come after it.  The subject is what does the action of the verb and the object is what receives the action.  In the sentence Bob ate a humburger, Bob is the subject or the one who did the eating and the hamburger is the object or what got eaten.  A verb which has an object is called a transitive verb and some examples are throw, buy, hit, love.  A verb which has no object is called an intransitive verb and some examples are go, come, walk, listen.

As you can see in the charts above, verbs are often made up of more than one word. The future forms, for example, use the word will and the perfect forms use the word have.  These words are called helping or auxiliary verbs.  The word be can serve as an auxiliary and will and shall are also auxiliary forms. The chart below shows two other verbs which can also be used as auxiliaries:
 

Number	Person	Present	Past
Singular	1st (I)	have do	had did
	2nd (you)	have do	had did
	3rd (he, she, it)	has does	had did
Plural	1st (we)	have do	had did
	2nd (you)	have do	had did
	3rd (they)	have do	had did

There is a type of auxiliary verb called a modal which changes the meaning of a verb in different ways.  Words like can, should, would, may, might, and must are modals and are covered in other lessons.