Apostrophe in possessives

Possessive nouns usually indicate ownership:

Example sentence: * Tim's hat * the lawyer's desk

Frequently, however, ownership is only loosely implied:

Example sentence: * the tree's roots * a day's work

If you are not sure whether a noun is possessive, try turning it into an of phrase: the roots of the tree, the work of a day.

Exercise: The apostrophe 1

Exercise: The apostrophe 2

Related topics:

Joint possession

Possessive compound nouns

Adding -s to an indefinite pronoun

Adding -s to a noun for possessive

Adding only an apostrophe to a noun for possessive