Generally, a possessive is formed by adding an apostrophe and an s to a word that does not end in s, and only an apostrophe to a word that does end in s.

Singular Plural
Brooks Brookses
child children
lunch lunches
sheep sheep
Sussex Sussexes
lady ladies
man men
passerby passersby
Singular Possessive Plural Possessive
Brooks’ Brookses’
child’s children’s
lunch’s lunches’
sheep’s sheep’s
Sussex’s Sussexes’
lady’s ladies’
man’s men’s
passerby’s passersby’s

Add an apostrophe to a word that ends in an s sound.
for old times’ sake
for conscience’ sake
for appearance’ sake

Add an apostrophe and an s to a foreign name ending in a silent sibilant.
Descartes’s invention
Des Moines’s schools
faux pas’s

Add an apostrophe and an s to the last word of a singular compound noun.
the Governor of Maine’s
the attorney general’s

Use an of phrase to show possession when both a plural and a possessive are involved in a compound noun.
RIGHT: the decisions of the attorneys general
WRONG: the attorneys general’s decisions

Indicate common possession by making only the last item in a series possessive.
Teddy, Peggy, and Nancy’s home

Indicate individual possession by making each item in a series possessive.
Teddy’s, Peggy’s, and Nancy’s homes

The following possessives should be written as singular per Web. 11. (updated 11/21/14)
baker’s yeast
printer’s ink
writer’s cramp

The following possessive should be written as plural per Web. 11. (updated 11/21/14)
confectioners’ sugar

Consider that in some cases words are not possessive but rather descriptive. In those cases, no apostrophes are needed. See descriptive words for more detail. (added 12/3/14)


Descriptive words

Back to BHG Stylebook Table of Contents

Comments are closed.