From "A Practical English Grammar"

Thomson and Martinet

Oxford English

15    Use of the possessive/genitive case and of + noun

A     The possessive case is chiefly used of people, countries or animals as shown above. It can also be used:

1      Of ships and boats: the ship�s bell, the yacht�s mast

2     Of planes, trains, cars and other vehicles, though here the of construction is safer:

a glider�s wings or the wings of a glider

the tram�s heating system or the heating system of the train

3     In time expressions�

a week�s holiday          today�s paper                 tomorrow�s weather

in two years� time        ten minutes� break         two hours� delay a ten-minute break, a two-hour delay are also possible: We have ten minutes� break/a ten-minute break

4     In expressions of money + worth:

�l�s worth of stamps      ten dollars� worth of ice-cream

5     With for + noun + sake: for heaven�s sake, for goodness� sake

6     In a few expressions such as�

a stone�s throw      journey�s end      the water�s edge

7     We can say either a winter�s day or a winter day and a summer�s day or a summer day, but we cannot make spring or autumn possessive, except when they are personified: Autumn�s return.

8     Sometimes certain nouns can be used m the possessive case without the second noun, a/the baker�s/butcher�s/chemist�s/flonst�s etc  can mean �a/the baker�s/butcher�s etc. shop�.

Similarly, a/the house agent�s/travel agent�s etc. (office) and the dentist �s/doctor �s/vet �s (surgery):

You can buy it at the chemist�s        He�s going to the dentist�s Names of the owners of some businesses can be used similarly:

Sotheby�s, Clandge�s

Some very well-known shops etc call themselves by the possessive form and some drop the apostrophe: Foyles, Harrods

Names of people can sometimes be used similarly to mean �      .�s house�:

We had lunch at Bill�s.       We met at Ann�s.

B     of + noun is used for possession.

1     When the possessor noun is followed by a phrase or clause.

The boys ran about, obeying the directions of a man with a whistle. I took the advice of a couple I met on the train and hired a car

2     With inanimate �possessors�, except those listed in A above:

the walls of the town      the roof of the church      the keys of the car However, it is often possible to replace noun X + of + noun Y by noun Y + noun X in that order:

the town walls      the church roof      the car keys The first noun becomes a sort of adjective and is not made plural:

the roofs of the churches = the church roofs (see 16) Unfortunately noun + of + noun combinations cannot always be replaced in this way and the student is advised to use of when in doubt.