A1 · Beginner

Whose Is It?

Tom's car, the boys' room, the door of the house. The little apostrophe-s claims ownership — and knowing when to use of instead is half the game.

01

What are Possessives?

Four ways to say whose

English claims things with 's (people), with of (things), and with a bare apostrophe (groups). Same idea, four costumes.

👤

's for people & animals

one owner → 's

Tom's car · the dog's tail

👥

s' for plural groups

many owners → apostrophe only

the boys' room

📦

of for things

the X of the Y — formal but safe

the door of the house

's for time

time owns things too

today's news · a week's holiday

⚠️ Live beings get 's; objects get of.

02

The Apostrophe Rules

Where the little hook goes

The apostrophe is a tiny letter but a big signal. One owner, many owners, or an irregular plural — the hook moves accordingly.

1

One owner: add 's

any singular noun

Tom's car · the cat's bowl

2

Many owners: add '

regular plurals already have -s

the boys' room · the students' books

3

Irregular plural: add 's

children, men, women have no -s

the children's toys · the men's team

4

Names ending in -s: 's

James, Charles — say it, then write it

James's house · Charles's bike

⚠️ The apostrophe goes where the owner goes: one owner, one apostrophe-s.

03

Common Mistakes

Five traps to escape

The apostrophe's favorite hiding spots: forgotten hooks, hooks in the wrong place, and of where 's belongs. Here is the escape.

This is my sisters bag.

This is my sister's bag.

💡 One owner → 's: sister's.

The childrens toys are here.

The children's toys are here.

💡 Irregular plural children has no -s → add 's.

The students's books are new.

The students' books are new.

💡 Students is already plural → apostrophe only, no extra s.

The cars of the men are red.

The men's cars are red.

💡 People take 's: the men's cars.

Today news is surprising.

Today's news is surprising.

💡 Time takes 's: today's news.

04

Quick Quiz

Test what you just learned

Three minutes, five questions — check what stuck. No essay questions, we promise.

Question 1 / 50 / 5

This is my ___ bike.

💡 Extra info2 sections
05

's or of?

Who owns it decides the pattern

People and animals take 's; things take of. Match each pair — both forms mean the same, but only one sounds natural.

Tom's car
the car of TomPerson → natural with ‘s.
the door of the room
the room's doorObject → natural with of.
the dog's bowl
the bowl of the dogAnimal → natural with ‘s.
the end of the day
the day's endAbstract → natural with of.

⚠️ Both are possible — the trick is what sounds natural. People: 's. Things: of.

06

Time with 's

Time owns things too

A day can own a plan, a year can own a holiday. Time expressions take 's like people do — one of the most surprising rules.

Time + 's
today's newstomorrow's meetingyesterday's matcha week's holidaytwo hours' walkthis year's sales
Fixed time phrases
in a minuteat the momenton Fridayby tomorrow

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