How to Use Apostrophes in Your Writing

After commas, apostrophes are probably the most troublesome of the punctuation marks for writers, both beginning and professional. The primary purpose of the apostrophe has two main functions; indication of omitted letters or numerals and to form the possessive of words. On very rare occasions an apostrophe can be used to make the plural form of a word. In some writing, mostly fiction, apostrophes can be used in place of omitted letters when writing dialects.

Forming possessives

This is perhaps the most common use of the apostrophe. The general rules for using apostrophes to form possessives are:
1. For most singular nouns an apostrophe with the letter "s" is added to the end of the word.
2. For plural nouns that already end in "s" normally just an apostrophe is added to the end of the word.
3. For plural nouns that don't end in "s" add an apostrophe and "s" to the end of the word.

Here are some examples of use of the apostrophe to form possessives:

Singular Nouns

John's bicycle is missing

In the Bible, Jesus's words are considered sacred.

Mr. Jones's new car is a Mustang.

(Note: Singular words ending in "s" take the apostrophe with an "s" at the end. One of the most common mistakes beginning writers make is to add only the apostrophe: e.g., Jesus' sermon in the Temple was very profound for a young boy.)

Plural nouns ending in "s"

The disciples' loyalty was important.

The athletes' urine tests were all positive. (Note: As opposed to the athlete's urine test was positive)

The witnesses' statements were rebutted by the evidence.

Plural nouns that don't end in "s"

Women's rights were an important part of her platform.

The People's Republic of China is the most populous country in Asia.

Deer's antlers are used for defense and offense.

There are exceptions to the rules of forming possessives for words that end in an eez sound (Ramses, Hercules); singular proper nouns that are formed from a plural word (New York Mets, United Nations. For these words, the possessive is formed by adding only an apostrophe at the end, except for the abbreviation of singular proper nouns, in which case, an apostrophe "s" is added. For example: The United Nations' announcement yesterday. The UN's announcement yesterday. Never use the apostrophe when writing possessive pronouns such as theirs, ours, yours, or hers.

Indicating omitted letters or numbers

The most common omission of letters in words is when contractions of verbs are used. In most cases contractions, because they sound less formal, are preferred to the fully written word. Whether you're writing fiction or nonfiction, using a contraction can add a sense of informality and credibility to your sentences. Care must be exercised, however, not to confuse readers, particularly those for whom English is not the native language.

Here are some examples of use of the apostrophe for indicating omitted letters:

"I simply can't make dinner tonight," Alice said. "I'm just too busy."

"I don't give a fig what you think; I plan to do it anyway."

Both of these sentences have an informal sound, much like what the average person might say. If, on the other hand, you were striving for a different mood in your writing, you might want to spell the words fully. Read the following versions and you can see the difference:

"I simply cannot make dinner tonight," Alice said. "I'm just too busy."

"I do not care what you think. I plan to do it my way."

As you can see, the second pair of sentences suggests a totally different mood, and the mental image you get of the speaker is decidedly different, so keep that in mind as you write.

Exercise caution when using contractions such as should've or could've in your writing as these can cause confusion for both native and non-native English speakers.

Another use of apostrophes to indicate omitted letters is the writing of dialect. This is difficult for many writers to pull off, and can offend some readers. In a short story I wrote about a streetwise punk who visited relatives in the south, I used this technique a lot to show differences in speech patterns. While the story was generally well received, a few of my southern readers thought I was insulting to the southern characters in the way I had them speaking. For instance, in one paragraph, I had a character say, "G'don in," Buck said. "I'm gonna Ca'thage." This was meant to translate as "Get on in," Buck said. "I'm going to Carthage." Now, while this sounds authentic when read aloud and slowly (which is how the people of the region about which I was writing actually speak), it didn't go over too well with a few readers. This is not to say that you should never attempt to write dialect; just beware that not every reader will get it.

Showing omitted numbers

When you write about a decade it is common to omit the century and substitute an apostrophe; ex: The music of the '60s was the best of all. A word of caution here; make sure the century you've omitted is clear from the context. The following sentence could easily be misunderstood. "The '60s was a time of turmoil." Will the reader know whether you're referring to the 1960s, the 1860s or the 1760s? Unless other text in close proximity to this sentence, or the general subject of your writing, makes it crystal clear, you're probably better served by changing this sentence to read, "The 1960s was a time of turmoil."

Using apostrophes to form plurals

Plurals don't normally take an apostrophe even when they are abbreviations or acronyms. The exception to this rule is the plurals of letters or words if they are confusing without the apostrophe. Examples of the use of apostrophes to form plurals are:

Mind your P's and Q's.

The Three R's are reading, writing, and 'rithmetic.

References:

http://grammar.ccc.commnet.edu/GRAMMAR/plurals.htm

http://www.grammarbook.com/punctuation/apostro.asp

http://www.fourmilab.ch/documents/apostrophe