Their
Their is a possessive determiner and a possessive pronoun in Modern English. It denotes ownership or association with a subject that is referred to by they, either as a plural group or as a gender-neutral singular.
As a possessive determiner, their appears before a noun: their house, their idea, their team won. It
As a possessive pronoun, theirs stands alone or follows a form of be: The book is theirs.
The use of their reflects the current practice of gender-neutral language. They can serve as a gender-inclusive
Common confusions include mixing up their with there (place) and they're (they are). They are often distinguished