Correct Use of Apostrophes in a Sentence

Correct use of apostrophes can be tricky business. How can such a small punctuation mark cause so much trouble? The apostrophe is frequently misused; all too often student writers omit apostrophes where they are necessary or include them where they are not. Here are a few guidelines for when, and when not, to use apostrophes.

When to use an Apostrophe

• To show possession: If the subject is singular, then show possession with an apostrophe followed by s; for example, "the cat's bed" or " Amy's book." This also applies to plural nouns that do not end in s; for example, "the children's school" or "the women's dresses." Here's where it gets a little tricky. If you have a plural noun that ends in s, such as "dogs," then to show possession you would use an apostrophe, without an additional s: "the dogs' toys." This also applies to singular nouns ending in s, for example, "octopus' garden" or "Mr. Jones' car."
• For contractions: When two words are combined to form one shortened word, it's known as a contraction. Examples are "you're" (you are) or "she's" (she is). In this case, the apostrophe is used in place of the letters that have been taken out to form the contraction.
• In dates: It's sometimes common to drop the first two digits of a date when you're referring to a decade. The apostrophe always appears before the number, not between the number and the letter s, as in the '70s, the '80s, etc. Don't make these date contractions posessive; you'll wind up with two apostrophes, as in "that '70's style," which looks confusing. Using "that 1970's style" is much easier on your readers' eyes. 

When Not to Use an Apostrophe

• The dreaded its: One of the most common apostrophe mistakes is confusing "it's," the contraction "it is," with "its," the possessive pronoun. Contractions always contain and apostrophe, so use one when you're shortening "it is." Possessive pronouns, such as its, hers, his, yours and ours, should never have an apostrophe.
• Plurals: When adding the letter s to a word to make it plural, as in the words bugs, antonyms, books and elephants, you do not use an apostrophe. Adding apostrophe and the letter s to a noun makes it possessive, not plural, thus changing your sentence's meaning completely.
• Quotes: Direct quotations need quotation marks. Apostrophes are not interchangeable with quotation marks. Using them in this manner is incorrect. There is one exception to this, which is when you are showing a quotation within a quotation. For example: Eleanor said, "Dad always told us, -The early bird catches the worm' to get us out of bed in the morning."

Once you learn these rules, using apostrophes will seem easy. Always ask yourself if something is plural or posessive. If it's possessive and it's not a pronoun, then it wants to own an apostrophe.