Possessive nouns

1. Possessive nouns generally show a relationship of ownership. The possessive form is used with nouns referring to people, groups of people, countries, and animals. To form the possessive, we add apostrophe + s ('s) to the noun: 

• John's car (the car of John)
• Women's clothes (clothes for women)
• Japan's seafood (the seafood of Japan)
• The cat's ears (the ears of the cat)

2. If the noun is plural, or already ends in 's', we can just add an apostrophe (') after the s (this is more common than adding 's).

• James' car / James's car (both are correct, but "James' car" is more common)
• The boys' room / The boys's room (both are correct, but "The boys' room" is more common)

3. Possessive nouns can also express where someone works, studies or lives

• Jane's company (the company is not owned by Jane, she just works there)
• Mark's school (the school is not owned by Mark, he just studies there)
• Susie's town (the town is not owned by Susie, she just lives there)

4. They also express relationships between people

• Lucy's mother
• Danny's girlfriend

5. Possessive nouns can also be used with immaterial things

• Tom's patience is running out
• Mary's opinions are similar to mine

6. When there are two or more owners, the possessive defines whether each or all members are the owners

• David and Emily's house (the house is owned by David and Emily)
• David's and Emily's houses (David owns a house and Emily owns a different one)