An apostrophe is a punctuation mark (') used to indicate possession or omission
Possession of singular nouns
To show possession of a single noun, the apostrophe + s is added to the following:
- noun that end in –s: actress's role; princess's lover; rhinoceros's skin.
- noun or name: uncle's pipe; George's girlfriend; dog's tail; Thomas's car.
- person's office or shop: I'll buy the pork at the Friendly Butcher's. / I'll be visiting Tom's.
- only after the second name to show joint ownership: Jack and Jill's pail; Bonnie and Clyde's
- both names to indicate separate ownership: Jack’s and Jill’s cars.
Possession of plural nouns
To show possession of a plural noun, the apostrophe + s is added to the following:
- plural nouns (owners) that end in –s: boys' bicycles; friends' houses; books' covers.
- plural nouns (owners) that do not end in –s: children's toys; women's clothes; men's boots.
- plural of abbreviations: many Dr.'s; many M.D.'s; many Ph.D.'s.
- plural of a letter: Your p's, and c's are too big. / You must dot your i's and cross your t's.
- plural of word or phrase: There are too many I’s and "you know’s" in his speech.
An apostrophe + s is used to show letters or numbers that have been left out.
Omission of letters
- Using apostrophe to contract words: I'm = I am; we’re = we are; don’t = do not; can’t = cannot: rock ’n’ roll = rock and roll.
- Using ‘s for is and has: he’s = he is/he has; it’s = it is/it has.
- Using ’d for had and would: they’d = they had/they would; she’d = she had/she would.
In short answers, we can omit the noun if it is not necessary to repeat it.
- Is that your coat?
- No, it’s Sandra’s.
- Where is Tom?
- He's at Noble Hardware's with dad.
Omission of numbers.
To show plural of a number:
To show that a number has been left out:
- My grandfather died in '86.
- My grandfather died in 1986.
To show the plural of a number that has been left out:
- The uprising happened in the '60's.
- The uprising happened in the 1960's.
Apostrophe + s used with singular noun.
- To show time: The workers took an hour’s break for lunch.
- To show time: The library is just fifteen minutes’ walk from my house.
- To show day: Why do you give me yesterday’s newspaper when it should be today's.
- To show week: We will be away on a week’s trip to the uninhabited island.
- To have double apostrophes: We were at James’ (or James’s) father’s office when he called.
Apostrophe + s used with compound noun.
- No: My mother's-in-law waistline is expanding fast.
- Yes: My mother-in-law's waistline is expanding fast.
When apostrophe + s is not used to show possession
So far the noun or nouns to which the apostrophe + s is added to show possession has/have been living things. For non-living things, the apostrophe + s is not used. Instead, of the is used to show something is part of a non-living thing. The reason for this is that unlike living things, non-living things cannot own things.
- No: Your car's windscreen wipers need to be replaced.
- Yes: The windscreen wipers of your car need to be replaced.
- No: The air was black from the factory's smoking chimney.
- Yes: The air was black from the smoking chimneys of the factory.
- No: Look, the shovel's handle must be held like this.
- Yes: Look, the handle of the shovel must be held like this.