Apostrophes & Possessives

Apostrophes should be used in the following instances:

  1. To indicate possession
  2. To mark contractions

Note: An apostrophe is typically not used to pluralize numbers, abbreviations, letters, or words used as words.  Do not use an apostrophe to pluralize numbers (including decades) or abbreviations, for example, “the 1980s,” “figure 8s,” or “IOUs”.  For plural letters, an apostrophe is optional, depending on the style, but always use italics: “two Ds were part of the logo,” or “two large D’s were part of the logo”.  MLA recommends an apostrophe; most important is to be consistent in your writing.  To pluralize words used as words, italicize the word and add an “s”: “ifs“, “maybes,” “buts“.

Forming the possessive of a singular noun

Most singular nouns become possessive when –‘s is added.

Ex: textbooks of the student → the student’s textbooks

the color of the bus → the bus’s color

the pencil belonging to my tutor → my tutor’s pencil

However, if adding –’s makes for three closely bunched –s sounds, use only the apostrophe.

Ex: the words of Moses/Ulysses/Jesus → Moses’/Ulysses’/Jesus’ words

Forming the possessive of plural nouns

If the plural noun ends in an –s, add just an apostrophe.

Ex: the muse of the writers → the writers’ muse

the opinions of the citizens → the citizens’ opinions

If the plural noun does not end in an –s, follow the rules for forming the possessive of a singular noun.

Ex: the toys belonging to the children → the children’s toys

the wings of the geese → the geese’s wings 

Forming the possessive for more than one noun

If two or more words possess an object, only the last word should be in possessive form.

Ex: the home where both George and Sally live → George and Sally’s home

Forming the possessive of a hyphenated term

If hyphenated words possess an object, only the last word in the cluster should be in possessive form.

Ex: the hobby of my father-in-law → my father-in-law’s hobby

Possessive forms for pronouns

The following pronouns are already possessive and should not be used with an apostrophe: his, hers, its, ours, ours, theirs, whose

Many writers get confused by “its” and “whose”.  When “it is” and “who is” are abbreviated, an apostrophe must be used: its, it’s, whose and who’s each mean different things.

Examples of “its”, “it’s”, “whose” and “who’s” used correctly:

Please take the dog for its walk.

It’s (It is) your turn to take out the trash.

Whose shoes are on the couch?

Who’s (Who is) invited to your birthday party?

To mark contractions

Use an apostrophe in place of missing letters: “It’s too bad”, “I can’t go”, “Don’t you agree?”.  Also use an apostrophe to show the omission of the first two digits of a year or years: “the class of ’18” or “the ’50s generation”.