10 rules for using the apostrophe

Last week, I tackled a controversial topic — the comma.

There are definite rules for its use, but many writers use commas subjectively, leading to disagreement (and acrimony) whenever writers or editors discuss this modest punctuation mark.

This week, I’m tackling another punctuation mark—the apostrophe. The rules for the apostrophe are much more definite, but they are frequently misapplied. So misunderstanding often ensues when it comes to the apostrophe.

Here are some rules for its use.

1. An apostrophe is used to show the possessive case of proper nouns.

• Allison Jones’ article (one person named Jones)
• The Joneses’ article
(two or more people named Jones)

2. If a singular or plural word does not end in s, add ’s to form the possessive.

• a child’s wants
• the men’s concerns
• the people’s choice
• everyone’s answer

3. If a proper noun or name ends in a silent s, z, or x, add an ’s

• Theroux’s “The Mosquito Coast”

4. Do not use ’s with possessive pronouns: his, hers, ours, its, yours, theirs, whose.

• The article was hers.
• I have not seen its equal.

5. Use ’s only after the last word of a compound term.

• my father-in-law’s book
• an editor in chief’s decision
• someone else’s problem

6. When showing joint possession with an organization’s or business firm’s name, use the possessive only in the last word.

• the Food and Drug Administration’s policy
• Hammond and Horn’s study

7. Do not use an apostrophe to indicate the plural of a name, an all-capital abbreviation, or of numerals.

• Veterans Affairs
• musicians union
• ECGs
• WBCs
• a woman in her 40s
• during the late 1990s
(1990’s—no, no, no, a thousand times no.)

8. Use ’s to indicate the plural of letters, signs, or symbols when s alone would be confusing.

• Please spell out all the &’s.
• She got eight A’s and two B’s on her last report card.

9. When units of time or money are used as possessive adjectives, add ’s.

• a day’s wait
• a dollar’s worth
• six months’ gestation
• two weeks’ notice
(The movie title was not punctuated correctly.)

 

RELATED: 7 movie titles that need to be proofread

10. When a word ends in an apostrophe, no period or comma should be placed between the word and the apostrophe.

• The last book on the shelf was the Smiths’.

 

Readers, care to share any egregious apostrophe errors you’ve seen lately?

 

This article was first published on Ragan Communication’s PR Daily.

 

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