Possessive Case
Possessive case expresses possession or relationship: nouns commonly use apostrophe forms, while possessive pronouns use their own forms without possessive apostrophes. Do not transfer noun-apostrophe rules to possessive pronouns: standard possessive pronouns do not take an apostrophe simply because they express possession.
Possessive case expresses possession or relationship: nouns commonly use apostrophe forms, while possessive pronouns use their own forms without possessive apostrophes.
Key details
Important caveats
Scope Boundary
Do not transfer noun-apostrophe rules to possessive pronouns: standard possessive pronouns do not take an apostrophe simply because they express possession.
Further guidance
Application
For nouns, apply the appropriate apostrophe pattern for singular and plural forms; for pronouns, choose the correct possessive form such as “my/mine” or “their/theirs.”
Core Rule
Possessive case expresses possession or relationship: nouns commonly use apostrophe forms, while possessive pronouns use their own forms without possessive apostrophes.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Pronoun Case — Purdue OWL (opens in a new tab)Purdue Online Writing Lab · Institutional grammar guidance identifying possessive case and possessive pronoun forms.
- Possessives: nouns — British Council LearnEnglish (opens in a new tab)British Council · Grammar guidance for forming noun possessives with apostrophe-s, plural apostrophes, and irregular plural possessives.