What is the possessive form of 'they'?

Answer 1

The possessive forms of the third person, plural pronoun 'they' are:

theirs, a possessive pronoun, a word that takes the place of a noun that belongs to someone or something.

Example: The Smiths live on this street. The house on the corner is theirs.

their, a possessive adjective, a word that is placed before a noun to show that the noun belongs to someone or something.

Example: The Smiths live on this street. Their house is on the corner.

Answer 2

There are two types of pronouns that show possession:

A possessive pronoun is a word that takes the place of a noun that belongs to someone or something. The possessive pronoun for the personal pronoun 'they' is theirs.

A possessive adjective is a word that is placed before a noun to describe that noun as belonging to someone or something. The possessive adjective for the personal pronoun 'they' is their.

Examples:

The Murphys live on this street. The house on the corner is theirs. (possessive pronoun)

The Murphys live on this street. Their house is on the corner. (possessive adjective)