Personal pronouns refer to people with one exception: it. The third person pronoun it although included in personal pronouns does not refer to a person; it usually refers to an animal or a thing. Personal pronouns are best explained by the table that follows.
What is shown in the table above is that personal pronouns have person, number, gender and case. The personal pronoun must be of the same number, gender, person, and in the same case as the noun for which it represents.
Personal pronouns have three grammatical persons: first-person (singular: I, me / plural: we, us); second-person (singular: you / plural: you) or third-person: (singular: she, her, he, him, it / plural: they, them).
First-person and second-person personal pronouns do not show gender. Only third-persons have gender: (masculine: he / feminine: she / neuter: it). The pronoun must agree with the noun in gender that it represents. If the noun is in the feminine gender, the pronoun too must be in the feminine gender. Likewise, if the noun is in the masculine gender, the pronoun must be in the masculine gender.
A subjective pronoun is in the subjective case when it is used as the subject of the sentence. The personal pronouns that can be used as subjects are I, you, he, she, it, we, and they.
An object or objective pronoun is in the objective case when it is used as a direct object, an indirect object, or an object of the preposition. The personal pronouns that can be used as objects are me, you, him, her, it, us, them.
For more on case, see case in glossary.