Judy Nollet
White Plume Communications

writer, instructional designer, eLearning developer

The Four Horsemen of the Apostrophe

Consider the apostrophe. This seemingly simple punctuation mark is consistently misused. For example, many retailers incorrectly add apostrophe-s ('s) to create plurals, for example, "Melon's On Sale." This mistake is so common that it is called "the greengrocer's apostrophe."

So when is an apostrophe appropriate? Here's a review of that forgotten English class. Keep this information in mind, and you'll never need to apologize for your apostrophes.

Showing Possession

Indicate ownership as shown in the table below.

Situation Add Examples
singular noun, including those that end in s 's the owner's office, Chris's computer
plural noun that ends in s ' the girls' party, the Joneses' house
plural noun that does not end in s 's the men's room, the alumni's contributions
indefinite pronoun 's someone's baggage, everybody's ideas

Keep in mind that possessive pronouns (his, hers, yours, ours, theirs, its, whose) never include an apostrophe.

By the way, when there is more than one person or item, indicate individual ownership by adding the appropriate possessive ending to each (for example, Sarah's and Tom's cars, Wal-Mart's and Target's return policies).

To indicate joint ownership, add the possessive ending only to the last noun (for example, Bridget and Mark's wedding, Minnesota and Wisconsin's tuition reciprocity agreement).

Replacing Missing Letters

Contractions are shortened words or phrases with apostrophes used in place of missing letters or numbers (though not in place of missing spaces).

Full Word or Phrase Contraction
it is; it has it's
who is; who has who's
should not shouldn't
Ye Old Mill Ye Ol' Mill
1999 '99

Confusing a contraction and a possessive pronoun is a common mistake (for example, you're vs. your; it's vs. its; who's vs. whose). When in doubt, try "de-contracting" the word or phrase to see if it makes sense.

Creating Special Plurals

Most plurals are created by adding s (girl-girls) or es (loss-losses), changing a y to ies (berry-berries), or making another designated change (child-children). There is another standard rule for the plural form of letters, numbers, symbols, and words referred to as words. In these cases, create a plural by adding 's. This rule has traditionally been applied to abbreviations, as well.

Form Example
letter Mark incorrect items with X's.
number The 9's all looked like 4's.
symbols Spammers search for @'s to find email addresses.
words referred to as words His speech was littered with like's.
abbreviation These M.D.'s and Ph.D.'s all graduated from the University of Minnesota.

Modern usage, however, doesn't always follow traditional rules. For example, there are many who drop the periods from abbreviations (MD, PhD). Strict grammarians still insist that those plurals should end in 's (MD's, PhD's). But, nowadays, many don't bother with the apostrophe in plural abbreviations (MDs, PhDs) or plural characters (Xs, 4s, @s) either. In other words, this has become a style issue. Whatever you decide, at least be consistent.

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