Independent possessive determiner
|First person singular||mine|
|First person plural||ours|
|Second person singular||yours|
|Second person plural||yours|
|Third person masculine singular||his|
|Third person feminine singular||her|
|Third person plural||theirs|
They are pronouns in the genitive case. As pronouns, they replace nouns, so e.g. in "It is John's", John's can be replaced with "his" to make "It is his". They are related to the dependent possessive determiners; my, our, your, his, hers and their. Both dependent and independent possessive determiners form a class of possessive determiners.
Third person singular independent possessive pronouns are very infrequently used; speakers may identify "its" and "one's" as filling these slots. However, we tend not to say ?"that is its", or ?"that is one's".