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.
Practical Application
Use possessive forms to show possession or another close relationship. Apply noun-apostrophe rules to nouns, but do not transfer those apostrophe rules to possessive pronouns.
Reader Check
First identify the word class. A possessive noun may need an apostrophe; a standard possessive pronoun such as “hers” or “theirs” does not take one merely to show possession.
Worked Example
Noun: “the editor’s notes.” Possessive pronoun: “The notes are hers,” not “her’s.”
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.