Follow these rules to create possessive nouns.
With singular nouns, add an apostrophe (’) and s.
girl: girl‘s manuscript
student: student‘s ideas
With plural nouns ending in s, add an apostrophe (’) after the s.
girls: girls’ manuscript
students: students’ ideas
boys: boys’ school
With plural nouns not ending in s, add an apostrophe and s.
women: women‘s books
mice: mice‘s tails
With compound nouns, add an apostrophe and s to the last word.
sister-in-law: my sister-in-law’s daughter
Possessives with of
We cannot put a possessive between a noun and a determiner. We can say my friend, his friend, John’s friend, a friend or that friend. But we can’t say a my friend or that John’s friend. Instead we use a structure with of + possessive.
Structure: determiner + noun + of + possessive
- He is a friend of mine.
- How is that brother of yours?
- He is a friend of my father’s.
- He is a cousin of John’s.
- Have you heard this new idea of the boss’s?
Note that sometimes we use a noun without the possessive ’s after of.
- He is a friend of my father.
- He is a cousin of John.