The only punctuation mark that causes more problems than the apostrophe is the comma, and that’s just because it is used more often.  Be the first person on your block to know how to use an apostrophe correctly!  It’s not that hard!

An apostrophe looks like a comma floating in the air: ’ .

Sometimes people see the letter “s” and stick an apostrophe next to it.  Don’t do that.  Correct apostrophe use is important because errors change meaning.  For example:

Mary’s refers to something Mary has.

Marys refers to more than one person named Mary.

Marys’ refers to more than one person named Mary and they both have something.

There are only two places where an apostrophe is needed:

• with a noun, to show possession:  Mary’s cat, the neighbor’s garage sale
• in a contraction, to indicate where letters or numbers have been left out:  didn’t, ’80s.

Possessives

To possess something is to own it.  Words that show possession are called “possessives.”  We use apostrophes to show possession.

To know where to put the apostrophe and whether or not to add an “s,” start by asking the question “Who or what does the possessing?”

• If the answer is a word that ends in a letter other than an “s,” add an apostrophe and an “s.”  For example: the children‘s toys, the doctor‘s visit
• If the word already ends in an “s” (for example, most plurals), add an apostrophe after the existing “s.”  For example: two birds‘ nest, the girls‘ bicycles
• Occasionally, a word that ends in “s” needs another sound to make the possessive clear.  For example: Texas’s border, the dress’s color, my boss’s instructions.  Say the word aloud.  If it needs another sound, you’ll hear it.  Add the apostrophe and another “s.”

Pronouns such as our, ours, your, yours, his, her, hers, its, their, theirs, and whose are already possessive and do not need apostrophes.  For example:

• their house
• her dog
• our religion

Contractions

To “contract” means to decrease in size.  When two words are shortened into one by removing letters and squeezing the words together, an apostrophe is added where the letters were removed.  For example:

is not → isn’t  (the apostrophe goes where the “o” was)

you have → you’ve  (the apostrophe goes where “ha” was)

Here are some common contractions:

One exception:  When making a contraction of “will not,” the pattern of just removing letters doesn’t hold true:

will not → won’t

In all other contractions, the apostrophe goes exactly where the letter or letters were removed.

Number Contractions

We also sometimes “contract” numbers.  The rule is the same:  put an apostrophe where the numbers have been removed.  For example:

He grew up in the ‘90s. (put the apostrophe where 19 was removed)

However, if the number is simply a plural, not a contraction, do not add an apostrophe.

The temperature is going to be in the low 40s.

Do NOT put an apostrophe between the number and the “s.” These are contractions, not possessives.

Commonly Confused Words

People often confuse these words:

• “its” (a possessive pronoun, as in “its paw”) and “it’s” (a contraction of “it is” or “it has”)
• “whose” (a possessive pronoun) and “who’s” (a contraction of “who is” or “who has”)
• “your” (the possessive pronoun, as in “your book”) and “you’re” (a contraction of “you are”)

Here’s a trick: If you can turn a contraction back into two words and the sentence makes sense, then it’s a contraction and needs an apostrophe.  For example:

The cat licked its paw.  (You would not say “The cat licked it is paw,” so “its” is a possessive pronoun, not a contraction.  No apostrophe.)

Who’s going to the party?  (You could say “Who is going” so this is a contraction and needs an apostrophe.)

The doctor said you’re to take the prescription.  (You would say “You are” so this is a contraction and needs an apostrophe.)

Notice that possessives work as adjectives and modify nouns.  For example:

Mary’s mother

our friends’ arrival  (This is a plural.  Several friends have arrived.  If only one friend arrived, it would be “our friend’s arrival.”)

the Jones’s address

their counselor’s office

a person’s clothes (singular)

people’s clothes (plural, but “people” doesn’t end in “s”)