There are four types of personal pronouns in English:

  1. subject pronoun: I, you, he/she/it, we, they
  2. object pronoun: me, you, him/her/it, us, them
  3. possessive pronoun: mine, yours, his/hers/its, ours, theirs
  4. possessive adjective.

All possessive pronouns can be used in place of proper nouns, common nouns, and other noun forms. Usually the noun has been mentioned previously. Subject pronouns are used in the subject position, while object pronouns are used as the object of either verbs or prepositions. Possessive pronouns are used alone (It is mine), while possessive adjectives go right before their nouns (It is my shirt).

Be careful: In the past, many people used “he” as a generic pronoun to refer back to nouns such as “a pilot.” However, this is becoming old-fashioned, and is being replaced by phrases such as “he or she” or “she or he,” and it is increasingly replaced by “singular they,” the use of “they” to refer to one, non-specific person. If none of these sound good to you, you can work around the problem by using a plural subject (“pilots”).