Singular nouns form their possessive case by adding ‘s to the singular.
- The boy’s dog
- My father’s office
Only the apostrophe (‘) without s is added if the noun contains too many hissing sounds.
- For goodness’ sake
- For conscience’ sake
- For Jesus’ sake
- Moses’ laws
Plural nouns ending in -s form their possessive case by adding only an apostrophe.
- Boys’ school
- Girls’ hostel
Plural nouns that do not end in -s, form the possessive case by adding ‘s.
- Children’s books
- Women’s club
Uses of the possessive case
The possessive case is now used chiefly with the names of living things.
- The lion’s mane
- The minister’s bodyguards
- The King’s palace
The possessive case is not normally used with the names of lifeless things; instead, we use a structure with of
- The leg of the table (NOT The table’s leg)
- The cover of the book (NOT The book’s cover)
- The roof of the house (NOT The house’s roof)
Exceptions
The possessive case is often used with the names of personified objects.
- Nature’s laws
- Fortune’s favourites
- At duty’s call
- At wit’s end
The possessive case is also used with nouns denoting time, space and weight.
- In a year’s time
- A day’s work
- At a stone’s throw
- A pound’s weight
The possessive of a proper noun denoting a trade, profession or relationship can often be used to denote a building or place of business.
- She has gone to the baker’s. (= baker’s shop)
- Tonight we are dining at Smith’s (= Smith’s house)