The apostrophe has a few simple uses that you need to know.
A. Use the apostrophe when forming the possessive case of nouns and indefinite pronouns.
The possessive case indicates ownership or possession. If the noun is singular (about one person, place or thing), form the possessive by adding an apostrophe and the letter s. For example,
You just ate out of the cat's dish.
That teacher's class is really hard.
For safety's sake, buckle your seat belt.
The class's performance was less than stellar.
Notice that this rule applies even when the noun ends in s.
An indefinite pronoun is a pronoun that doesn't refer to a specific person or thing, such as anyone, everybody, each, no one, or something.
If the noun is plural and ends in s, add only an apostrophe. If the noun is plural and doesn't end in s, add an apostrophe and an s. I know. This is one of those rules that makes you throw up your hands. But it's really simple.
The students' grades were listed in the newspaper.
He has had several years' experience.
The puppies' mother was solid white.
The children's parents are out of town.
Men's clothing is usually expensive.
The first three examples have plural nouns ending in s. Only an apostrophe needs to be added. The last two examples have plural nouns not ending in s. In those cases we need to add an apostrophe and an s.
To form the possessive case of a compound word or phrase, add an apostrophe and an s to the last word.
My mother-in-law's cooking left a lot to be desired.
That is somebody else's problem.
If two or more nouns have joint possession of something, add an apostrophe and an s to the last noun.
Jeanne and Mike's new car is a Subaru.
Kirk and Spock's friendship is legendary.
If two or more nouns each have individual possession of something, add an apostrophe and an s to each noun.
Jeanne's and Peg's houses face each other.
The president's and the congress's opinions are quite different.
There are several common errors people make when using the apostrophe to indicate possession.
Do not use the apostrophe to form possessives of personal pronouns. Personal pronouns include he, she, it, we, you, they, and who. Their possessive forms are his, hers, its, ours, yours, theirs, and whose. None of these have apostrophes.
I wonder whose iguana this is.
Have you taken its temperature?
I would rather take yours.
Many people use it's when they should use its and who's when they should use whose. The apostrophes in it's and who's do not indicate possession. That is incorrect, as we discussed above. They indicate a contraction. It's means it is and who's means who is.
B. Use the apostrophe in contractions and to indicate missing letters, words, or numbers.
A contraction is a two-word combination that uses an apostrophe to signal where letters have been omitted. Here are some examples.
He's the president of the club.
I can't go to the store.
(can't stands for can not)
I wouldn't betray you.
(wouldn't stands for would not)
In each case, one or more letters have been removed and replaced with an apostrophe. An apostrophe can also be used to indicate missing words or numbers.
My iguana was born in '92.
The '60s were a wild time.
It is five o'clock.
(o'clock stands for of the clock)
C. Use the apostrophe to form the plural of letters, symbols, abbreviations, and words used as words.
To form the plural of letters or words used as words (rather than for their meaning) add an apostrophe and an s. This is easiest to explain by giving you some examples.
That teacher wants you to dot your i's and cross your t's.
The exercise on apostrophes told when to use s's.
His paper has too many but's in it.
Note that letters or words used as themselves are always either underlined or set in italics. But the apostrophe and the s are not.
Similarly, to form the plural of symbols or abbreviations, add an apostrophe and an s.
Her computer would print only *'s.
Fifty Ph.D.'s attended the conference.
Exercises for Part 4
Here are some exercises covering what you've just learned about the apostrophe. Insert apostrophes where necessary and make corrections where necessary.
- Iguanas are fascinating creatures.
- What is the schools mascot?
- Its not an iguana, thats for sure.
- Whose saying that it was?
- The students top choice was a spider.
- That attracted the medias attention, including the television stations and the newspapers.
- The student councils representative was on the six oclock news.
- I can't believe its all happening.
- Sallys and Janes little iguana started the whole thing.
- Sallys ts look like os.
- This could only happen in the 90s.