Grammar › Nouns & Determiners › Possessives: 's vs of
Possessives: 's vs of
Choose 's or 'of' mainly by whether the owner is a person/animal or a thing:
- 's — people, animals, groups, time (my sister's car, a week's holiday).
- of — things and abstract nouns (the leg of the table, the start of the year).
Plural nouns ending in -s take just an apostrophe: the teachers' room. Singular nouns add 's: the boss's office.
’s or of?
| Use ‘s | Use of |
|---|---|
| People: Anna’s bag | Things: the roof of the house |
| Animals: the dog’s tail | Abstract: the end of the story |
| Groups: the team’s win | Parts: the leg of the table |
| Time: today’s news, a week’s rest | Ideas: the cause of the problem |
When and how to use them
1. ’s — people, animals, groups, time
- Maria’s brother; the cat’s bowl; the band’s new album; a day’s work.
2. of — things and abstract nouns
- the handle of the door; the beginning of the year; the point of the meeting.
3. The apostrophe with plurals
- one boy → the boy’s ball; two boys → the boys’ ball; the children’s room (irregular plural).
⚠️ Singular names still add ‘s: James’s car, the boss’s office. Plurals ending in -s take just an apostrophe: the players’ changing room.
Common mistakes
1. ‘of’ with a person. the car of my brother → my brother’s car.
2. Apostrophe in the wrong place. the girls’s team → the girls’ team.
3. ‘s for an ordinary thing. the table’s leg → the leg of the table. Pro tip: person/animal/group/time → ‘s; thing/abstract → of.
✏️ Practice: Possessives: 's vs of
1. This is ___ car.
2. Please close ___ .
3. Have you seen ___ news?
4. The ___ toys are all over the floor. (more than one child)
5. That's the ___ changing room. (the players, plural)
6. We can't see ___ from here.
7. It's ___ office. (the boss, singular)
8. After ___ rest, she felt better. (one week)
9. Correct this: 'The leg of the dog is hurt.'
10. Which owner normally takes 's?
Frequently asked questions
When do I use 's and when 'of'?
Use 's for people, animals and groups (Tom's phone, the team's coach) and time (yesterday's meeting). Use 'of' for things and abstract nouns (the door of the car, the meaning of the word).
Where does the apostrophe go with plurals?
For plurals ending in -s, put the apostrophe after the s: the girls' team, my parents' house. For irregular plurals (children, men), add 's: the children's toys.
Is it James' or James's?
Modern usage prefers James's for a singular name, though James' is also seen. Say the extra sound: 'Jamesiz car'.
Can I use 's with things?
Often it's more natural to use 'of' (the top of the box), but 's is common with organisations and places (the world's population, London's parks).
👩🏫 For teachers
CEFR objectives for “Possessives: 's vs of”:
- Can use 's for people/animals/groups and 'of' for things (CEFR A2).
- Can place apostrophes correctly with singular and plural nouns.
- Can use 's in time expressions (a day's work).
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