A conjugation of a verb is a list showing the different forms a verb may take. When a verb is conjugated, it is usually accompanied by all of the personal pronouns which can act as subjects of a verb. Thus, a conjugation can show the different forms a verb must take when it is used with different subjects.

The English personal pronouns which may be used as subjects of verbs are as follows:
 

It should be noted that in modern English, the same verb forms are used with the subject you, whether you refers to one or more than one person or thing. In an older form of English, there was another personal pronoun, thou, which was used with different verb forms, and which generally referred to one person or thing.

The Simple Present of the verb to be is conjugated as follows. In spoken English, contractions are often used.
 

In written English, an apostrophe: ' is used in a contraction, to indicate that one or more letters have been omitted.

a. Affirmative statements
An affirmative statement states that something is true. In an affirmative statement, the verb follows the subject.
e.g. I am awake.
      They are ready.

In the first example, the verb am follows the subject I. In the second example, the verb are follows the subject they. In written English, statements are always followed by a period: . Statements and questions must begin with a capital letter.

In order to review the preceding points, see Exercise 1.

b. Questions
For the Simple Present of the verb to be, questions are formed by reversing the order of the subject and the verb, so that the verb precedes the subject.
e.g. Am I awake?
      Are they ready?

In the first example, the verb am precedes the subject I. In the second example, the verb are precedes the subject they. In written English, questions are always followed by a question mark: ?

See Exercise 2.

c. Negative statements
In the Simple Present of the verb to be, negative statements are formed by adding the word not after the verb.
e.g. I am not awake.
      They are not ready.
In the first example, not follows the verb am. In the second example, not follows the verb are.

In spoken English, the following contractions are often used:
 

See Exercise 3.

d. Negative questions
In the Simple Present of the verb to be, negative questions are formed by reversing the order of the subject and verb, and adding not after the subject.
e.g. Am I not awake?
      Are they not ready?

In spoken English, contractions are usually used in negative questions. In the contracted form of a negative question, the contraction of not follows immediately after the verb. For example:
 

It should be noted that there is no universally accepted contraction for am not. In spoken English, am I not? is often contracted to aren't I?. However, although the expression aren't I? is considered acceptable in informal English, it is not considered to be grammatically correct in formal English. In formal English, no contraction should be used for am I not.

See Exercise 4.

e. Tag questions
A tag question is a question added at the end of a sentence. A tag question following an affirmative statement generally has the form of a negative question, with the meaning: Isn't that true? In some languages, such tag questions are invariable. However, in English, tag questions vary, depending on the verbs and subjects of the preceding statements.

In the following examples, the tag questions are underlined. Contractions are usually used in negative tag questions. For example:
 

These examples illustrate how the subjects and verbs of the preceding statements are repeated in tag questions. For instance, in the first example, the subject I and the verb am are repeated in the tag question. In the second example, the subject you and the verb are are repeated in the tag question.

In spoken English, the expression aren't I? is often used as a tag question. However, this is not considered to be grammatically correct in formal, written English.

See Exercises 5 and 6.