Page 174 - English Grammar in Use

Unit -’s (your sister’s name) and
81 of … (the name of the book)

A We use -’s (apostrophe + s) mostly for people or animals:
Tom’s computer isn’t working. (not the computer of Tom)
How old are Chris’s children? (not the children of Chris)
What’s (= What is) your sister’s name?
What’s Tom’s sister’s name?
Be careful. Don’t step on the cat’s tail.

You can use -’s without a noun after it:
This isn’t my book. It’s my sister’s. (= my sister’s book)
We do not use -’s after a long group of words. So we say:
my friend’s mother
but the mother of the man we met yesterday (not the man we met yesterday’s mother)
Note that we say a woman’s hat (= a hat for a woman), a boy’s name (= a name for a boy),
a bird’s egg (= an egg laid by a bird) etc.

B With a singular noun we use -’s:
my sister’s room (= her room – one sister)
Mr Carter’s house (= his house)
With a plural noun (sisters, friends etc.) we put an apostrophe (’) after s:
my sisters’ room (= their room – two or more sisters)
the Carters’ house (= their house – Mr and Mrs Carter)
If a plural noun does not end in -s (for example men/women/children/people) we use -’s:
the men’s changing room a children’s book (= a book for children)
You can use -’s after more than one noun:
Jack and Karen’s children Mr and Mrs Carter’s house

C For things, ideas etc., we normally use of:
the temperature of the water (not the water’s temperature)
the name of the book the owner of the restaurant

We say the beginning/end/middle of … / the top/bottom of … / the front/back/side of … :
the beginning of the month (not the month’s beginning)
the top of the hill the back of the car

D You can usually use -’s or of … for an organisation (= a group of people). So you can say:
the government’s decision or the decision of the government
the company’s success or the success of the company
We also use -’s for places. So you can say:
the city’s streets the world’s population Italy’s prime minister

E We use -’s with time words (yesterday / next week etc.):
Do you still have yesterday’s newspaper?
Next week’s meeting has been cancelled.
In the same way, you can say today’s / tomorrow’s / this evening’s / Monday’s etc.
We also use -’s (or -s’ with plural words) with periods of time:
I’ve got a week’s holiday starting on Monday.
Julia has got three weeks’ holiday.
I live near the station – it’s only ten minutes’ walk.

Noun + noun (a bus driver) ➜ Unit 80 a three-hour journey, a ten-pound note ➜ Unit 80E
162 -’s (= is or has) in short forms ➜ Appendix 5.2