Apostrophes
Apostrophes are used primarily in two ways: to show the omission of letters in a contraction, and to form a possessive noun.
A contraction is a shortened form of a word (or a group of words) that leaves out certain letters. Apostrophes are used in contractions to show that letters (or sometimes numbers) have been omitted.
Example: Keith couldn’t come to the picnic on Saturday.
An apostrophe is used in the word couldn’t to show that the words could and not are combined (or contracted), and that the letter o is omitted.
Some examples of other common contractions include don’t (do not), I’m (I am), she’ll (she will), who’s (who is), could’ve (could have), and ’90 (1990). Contractions are common in everyday speech and informal writing, but often are not used in academic writing.
Apostrophes are also used to form a possessive noun. A possessive noun is a noun—a person, place, or thing—that possesses something, or in other words, has something. A possessive noun generally indicates ownership.
Example: The dog played with the cat’s toys.
An apostrophe and an s are used to indicate that the toys belong to the cat.
There are a few rules to remember when using an apostrophe to show possession. For most singular nouns, like the cat in the example above, we add an apostrophe and an s to show possession.
For most plural nouns, however, we only add an apostrophe.
Example: The dog played with the cats’ toys.
In this example, the toys belong to multiple cats. Because the noun is plural and ends with an s, we only add an apostrophe.
There are some exceptions to these rules. For plural nouns that do not end with an s, we add an apostrophe and an s.
Example: The dog played with the children’s toys.
The plural form of child is children, which doesn’t end with an s, so to show that the toys belong to the multiple children we use an apostrophe and an s.
There are different recommendations of what to do when a proper noun’s singular form ends with the letter s. A proper noun is a noun that designates a specific person, place, or thing.
Example: The dog played with James’ toy.
In this example, the toy belongs to James. A name is a proper noun, and James ends with an s. Here we’ve shown possession by using only an apostrophe, but some style guides would recommend using an apostrophe and an s: James’s. If you’re writing academically, check the style guide that you’re required to use in your discipline (ex. MLA, APA, Chicago, etc.). If you’re not writing according to a style guide, choose to either use an apostrophe and an s or only an apostrophe in these situations, and be consistent.
Finally, we’ll review a few situations where you should not use an apostrophe. Personal pronouns, unlike regular nouns, don’t use apostrophes to form possessives. Personal pronouns are words that replace the people (or sometimes animals) that are referred to in a sentence. They include words like I, they, she, him, us, and them.
Example: The children took the toy because it was theirs.
In this example the toy belongs to the children. Instead of repeating the words the children multiple times in the sentence, which can sound awkward, we can refer to the children using the pronoun them. To show that the toy belongs to the children, we use the plural, possessive version of them, which is theirs.
We also do not use an apostrophe when pluralizing a word.
Example: The dog played with the toys.
The word toys is plural, and only needs an s added to indicate that. People often make the mistake of adding an apostrophe when making a word plural: toy’s is incorrect. The only exception to this rule is when writing about multiple lowercase letters.
Example: Dot your i’s and cross your t’s.
We use an apostrophe when writing a plural form of a lowercase letter to avoid confusion. Otherwise, a reader might read that sentence as dot your is and cross your ts and assume is and ts are both meant to be words, not the plural letters.
Practice:
Answers:
The guitar is hers.
The kids went on as many rides as they could at the amusement park.
Note: some style guides would require an additional s after the apostrophe (Dickens’s)
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