Objects of “to be” verbs must be in the subject form. Watch for pronouns following “to be” verbs (these include verbs such as “it should have been,” “it is,” “it could have been,” “it was,” etc.), and make sure they are in subject form. Note that this is an exception to the rule: normally, you would use the object form when the pronoun is the object of the verb.

This is another error common in speech, but it is simple enough to identify and correct as long as you are able to:

1) Identify a “to be” verb.
The verb “to be” takes many forms, some of which can be difficult to recognize as “to be” verbs. Look for the words am, are, is, was, and were, as well as constructions involving the words be, being, and been.

2) Remember the subject form of the pronoun.
Refer to the chart below for the different forms of personal pronouns.

Chart of Personal Pronouns: Subjective, Objective, and Possessive Forms
Subjective Objective Possessive
First Person Singular I me mine
Second Person Singular you you yours
Third Person Singular he/she/it him/her/it his/hers/its
First Person Plural we us ours
Second Person Plural you you yours
Third Person Plural they them theirs

Consider the following sentence:

It must have been (her / she) who called.

This sentence contains two pronouns, It and she. The pronoun It is the subject of the “to be” verb must have been, and the pronoun she is the object. Many casual speakers and writers of English do not know the rule about the “to be” verb and mistakenly use the object form of the verb, her: It must have been her who called. However, the “to be” rule requires the subject form: It must have been she who called. The pronoun she is correct.

When you see a “to be” verb followed by a pronoun, make sure that the pronoun is in the SUBJECT form!

The following key words will help you identify “to be” verbs:

  • am, is, are, was, were
  • be, been, being
Take five full-length GMAT CAT tests with video explanations and tutor support.