The 's-genitive

The s-genitive is used to express a possessive relation between two objects. For example, the sentence: "This is my friend’s book", expresses the idea that a book belongs to your friend.

Overview:

Explanation

Sometimes you will need to express a possessive relation between people or things. This means telling if someone/something belongs to someone/something.

In this case, you use an "'s" after the noun or the name. Take a look at the following example:

You have a book. But it is not your book, it is your friend's book. This means: the book belongs to your friend.

You add an 's to the noun that someone/something belongs to. Don't forget the apostrophe ' :

Anna's room: the room that belongs to Anna
her mother's bedroom: the bedroom that her mother sleeps in
the dog's coat: the coat that the dog has
the boy's bike: the bike that belongs to the boy
the woman's shoe: the shoe that belongs to the woman

If the noun is in the plural form and ends with the letter s, do not add another 's. Only add an apostrophe:

the boys' shirts: the shirts that belong to more than one boy
the girls' hats: the hats that belong to more than one girl
the schools' principals: the principals of many schools

Compare: the girl's hats: the hats that belong to one girl the girls' hats; the hats that belong to more than one girl

In spoken language, you can also use the 's-genitive without a noun following it, especially when you talk about a house or an apartment that belongs to someone:

I'm going to Johnny's. Then everybody knows that you talk about Johnny's place or house.
Meet me at Julia's.
I'm staying at Thomas' tonight.
I'm going to Maria's.
He's staying at the Smiths' today.

Note that when you want to form the s-genitive for a name that ends on "s", you have two possibilities: you can use "'s" or just the apostrophe. However, it is considered to be better English to use "'s". Therefore, you should stick to that in the exercises below.

Besides the s-genitive, there is also the of-genitive that you can use to express a possessive relation: