Page 446 - Practical English Usage 3ed - Michael Swan, Oxford

possessives (1): noun + 's (forms) 439
Policy is used for people's rules of behaviour (not necessarily connected with politics).
After the war, British foreign policy was rather confused. (NOT ••• British r..r.)
JtJFe'grt. I'tHt,es ...
It's not my policy to believe everything 1 hear.
It's the firm's policy to employ a certain number 0/ handicapped people.
439 possessives (1): noun + 's (forms) 1 spelling
singular noun + 's myfather's car
plural noun + ' my parents' house
irregular plural + 's the children's room, men's clothes, women's rights,
an old people's home
We sometimes just add an apostrophe (') to a singular noun ending in -s, especially in literary and classical references.
Socrates' ideas. Dickens's novels But's is more common.
Mr Lewis's dog
We can add's or ' to a whole phrase.
the man next door's wife Henry the Eighth's six wives the Smiths' new house
Note the difference between, for example:
Joe and Ann's children (one lot of children: Joe and Ann are their parents) Joe's and Ann's children (two separate lots of children: Joe's and Ann's)
2 pronunciation
The ending's is pronounced just like a plural ending (see 525).
doctor's /,dnktaz/
dog's /dngz/
president's /,prezrdants/
Madge's /'mmd3Iz/ Alice's /,mlIsIZ/
James's /,d3errnzIz/ Jack's /d3reks/
The apostrophe in a word like parents' does not change the pronunciation at all. But with singular classical (ancient Greek and Roman) names ending in s',
we often pronounce a possessive's even when it is not written. Socrates' /'Jnkrati:zlz / ideas.
3 possessive's and other determiners
A noun cannot normally have an article or other determiner with it as well as a possessive word (see 154). Definite articles are usually dropped when possessives are used.
the car that is John's (= John's car) (NOT the )trJh,,,'3 elir OR J8hn'3 the ear) But a possessive word may of course have its own article.
the car that is the boss's (= the boss's car)
When we want to use a noun with a!an or this!that etc as well as a possessive, we usually use the 'o/mine' construction (see 443).
She's a cousin ofJohn's. (NOT ••• ti }8.'1n'3 e6f:t3in.)
I saw that stupid boyfriend ofAngie's yesterday. (NOT ••• H1titAngie'3 3tupid
btJyfriend ...)
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