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5.1a More on Apostrophes

downloadable worksheet


The basic convention of the possessive apostrophe is straightforward: insert an apostrophe before an <s> and before another noun when that noun is owned by or “possessed” by the first noun.

            a child’s shoe

            your aunt’s house

And when the word is plural, so already ends in -s, the basic rules are still straightforward:

  • add -’s to a singular – cat’s hat

  • unless the word is a plural already ending in <s>, and then, just add an apostrophe – cats’ hats

So that seems easy enough – why then do some of us have problems? Because there is variation in how to do it “correctly” with some words. The standards vary. For example, what do you do when the word is singular (or a mass or collective noun), but ends in -s, such as molasses, hippopotamus, walrus, octopus, boss, or floss. Should an <s> be added after the apostrophe when these singular nouns indicate possession? Is it the boss’ friend or the boss’s friend? It actually depends on who (or whom!) you ask.  The Associated Press Stylebook recommends omitting the -’s after the apostrophe in singular words ending in <s>, but, The Chicago Manual of Style, says that if the <s> at the end of a singular word is pronounced, the possessive is formed by adding -’s. So pronunciation matters? To some, but not too others, so this leads to confusion about the rule. And what happens, for example, if it’s spelled with <x>, which is of course pronounced “ks”? It should probably be a fox’s tail, not a fox’ tail, don’t you think?


Is there any rule we can just agree on and follow? Yes, and it’s one of the most common errors in writing - the pronoun its, which is often written as it’s. None of the possessive pronouns or possessive determiners use apostrophes: mine, yours, his, hers, its, ours, theirs. (See Lesson 1.7a on pronouns and determiners.) Most of us would have no problem with this rule if it weren’t for the contraction of it and is to it’s; so we’re used to seeing the word it’s, and we know that apostrophes indicate possession. It’s an easy slip to make. Somewhat less common, but also prevalent is who’s instead of whose; Who’s hat is that? might not look so wrong, but the standard version would be Whose book, using the possessive determiner.


Is it its or it’s?


1. _____ about time you showed up!

2. It was _____ first time out of the cage.

3. _____ feet were covered with sand.

4. Get up, _____ time for school.

5. I’m glad to see you; _____ been a long time.

6. _____ important to study hard for tests.

7. The bear protected _____ cubs.

8. _____ my turn to go down the slide.

9. The dog seemed to like _____ new hair cut.

10. _____ too late to eat dinner.

11. My car is old and _____ paint is peeling.

12. The bird realized that the wind had blown _____ nest away.


[Teacher notes: Proper nouns seem to cause a host of other problems. Fowler’s Modern English Usage, first published in 1892, recommends omitting the <s> after the apostrophe only for names ending in an “iz” sound, as in Bridges’. Do they mean just “an iz sound”? What about just “z” as in Jones? Is it the Jones’ house or the Jones’s house? And this example is especially interesting because there is more than one way to pronounce it, with one syllable or two. And we seem to want to make the spelling with an additional <s> correspond to the additional syllable. So if you say “jownziz,” you might feel better spelling it Jones’s, but if you say “jownz”, you might want to spell it Jones’. And the style guides – some of them – will agree. Some of them try to simplify the rules, giving a single rule, but then you end up with words that just don’t seem to fit. And finally, a very strange rule of many style guides with respect to the possessive of proper names is that ancient names or important, historical, or classical names that end in <s> should end with an apostrophe alone; so, Moses’ sandals, Jesus’ friend, Venus’ name. But The Chicago Manual of Style, for instance, doesn’t follow this rule, offering Aristophanes’s plays and Zeus’s wife. Such a rule is, of course, subjective too, raising the question of how old is ancient or who should be considered important enough? One of the reasons there are so many “errors” of apostrophe usage is because there is a great deal of variation, even among writers of edited academic English.]



key words: punctuation, apostrophes, its/it’s, writing errors


CCSS.ELA-Literacy.L.3.1b Form and use regular and irregular plural nouns.

CCSS.ELA-Literacy.L.3.2d Form and use possessives. 


Here is this lesson as a pdf.

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