The Possessive Case (’s)
The Possessive Case is used to show ownership. The possessive pattern (’s) is generally used when indicates a relation of ownership or association with a person, rather than a thing. There are, as ever, exceptions to this rule.
The main rules are:
- For a singular noun, use ’s:
The girl’s mother.
The world’s highest tower.
Brazilian’s climate.
- For a plural noun which does not end in -s, use ’s:
Children’s right.
The men’s room.
An old people’s home.
- For a plural noun which ends in -s, use s’:
My parents’ car.
Your brothers’ ideas.
His classmates’ books.
- You sometimes just add an apostrophe to names ending in -s, especially with singular literary or classical names:
Dickens’ novels.
Socrates’ works.
Keats’ poetry.
We often pronounce a possessive ’s even when it is not written /siz/.
- An apostrophe ’s can be added to first names ending in -s:
Cris’s motorcycle.
Carlos’s computer.
Marcos’s Iphone.
- If the thing possessed belongs to more than one person, we add the ’s only to the last one:
Paul and Mary’s daughter.
Bob and Brad’s toys.
Rick and Susan’s apartment.
- However, if each person has their own object, we add the ’s to each one:
Mark’s and Sharon’s cell phones. (each one of them has a cell phone)
Greg’s and Carol’s bicycles.
Adapted from Gems of Wisdom