Punctuation Guide: When to Use an Apostrophe

ContractionsPluralLast namesPossessive apostropheAfter -sAfter -xPlural possesives

There are some punctuation signs in English that are responsible for only one or two functions. The apostrophe is one of them. Here’s the apostrophe definition—it’s a punctuation mark that shows possession, omission of letters, and sometimes plurals.

Take a look at these punctuation marks’ uses and examples:

Contractions

Contractions

Perhaps you have heard many times that contractions are bad, that you shouldn’t use them in your writing, and so on. But in real life, we often use them in everyday speech. So you should know how to write them, as well.

When to use punctuation of this kind? According to the apostrophe rules, there are specific words which can be contracted; for example, shouldn’t, he’s, let’s, wouldn’t, and so on.

Don’t mix up the contraction with the possessive form of a pronoun:

It’s the day he’ll see the car again—its roof must be repaired!

The apostrophe for plurals

The apostrophe for plurals

Every person, who learns punctuation and grammar, knows how to make plural forms from singular ones. The most challenging part here is to distinguish what ending to add: –es or –s.

But there are also some other times when you need apostrophes after -s to create plurals.

How to use apostrophes with plurals? Several proper names, days of the week, abbreviations, lowercase letters, and some other cases need apostrophes for plural forms:

You shouldn’t work in McDonalds’s all around the country when you have two PhD’s!

The apostrophe after last names

The apostrophe after last names

Notice that not every proper name uses an apostrophe. To make plurals of surnames, add the ending –es to those surnames which end with –s, for other surnames use the ending –s.

For example, the plural of Jones is Joneses, and the plural of Smith is Smiths.

The possessive apostrophe

The possessive apostrophe

To indicate ownership, English language speakers learn when to add an apostrophe.

To build a possessive form, just add –’s to the word:

Apple’s,son’s, audience’s.

The apostrophe after -s

The apostrophe after -s

If a proper noun ends with –s, add an apostrophe only:

Charles’, Texas’, Lois’.

If it’s not a proper noun, add an apostrophe with –s as always:

Cactus’s, bus’s, boss’s.

The apostrophe after –x

The apostrophe after –x

There’s a popular misconception about the omission of –s­ when building plural forms of words that end with ­–x.

Don’t believe this punctuation myth! Use the possessive ending as always:

Xerox’s, box’s, wax’s.

Plural possessives

Plural possessives

When the plural form ends with –s, add an apostrophe:

Books’, statues’, scientists’.

When the plural form doesn’t end with –s, compensate the ending with –’s:

Criteria’s, swordsmen’s, mice’s.

These apostrophe examples will help you to figure out your situation easily and choose the right form. Now you can distinguish possessives from contractions, give an apostrophe definition, and write plural forms correctly.

Read other sections of our punctuation guide to strengthen your writing skills and get an A on your next paper.