Commas are the mortar that holds sentences together. Too many or too few commas can severely damage the structure of your content. Luckily, there are definitive rules for comma usage; you just need to know when to apply each rule.

1. Commas and Conjunctions:
A basic comma rule is to use one in front of a coordinating conjunction that separates two complete sentences, such as, “Dave went to the bar, and he stayed until the end of the ballgame.” Since there is a clearly defined subject in each clause, the comma is necessary. However, if a subject is shared between clauses, then a comma is not used. This is seen in the sentence, “Dave went to the bar and stayed until the end of the ballgame.” The same rule applies to imperative sentences that imply the use of “you” as the subject. “Cook the apples, and add the sugar.”

2. Commas and Direct Quotations: A comma must be used to introduce a quote that contains a complete sentence. The first sentence in Example 1 below contains a quote that is a full sentence, so there must be a comma in front of the quotation. However, the second sentence has a fragment inside the quotations, so a comma is not needed to offset the quote (the introduction of a quote that is two sentences or longer requires a colon). If you are attributing a quote to a source, then place the comma inside the quote, as seen in the last sentence within the example.

  • Example 1: His famous last words were, “Serial commas are for the birds.”
  • Example 2: He thinks that commas are “for the birds."
  • Example 3: “Serial commas are for the birds,” he thought to himself.

3. Commas and Equal Adjectives:
Text Box: Example 2 – 1. Baseball players, who are elite in their profession, make more money than athletes in other sports. 2. Baseball players who are elite in their profession make more money than athletes in other sports. A rule that sometimes takes a little thought is placing a comma between equal adjectives. Saying “a long, winding road” requires a comma because the adjectives are equal in describing the road. “A long asphalt road” is an example of unequal adjectives. While “asphalt” describes the road, it is an essential part of the noun phrase. “The stylish, brightly colored baseball cap” uses three modifiers, but “baseball” outranks the other adjectives because it is essential to the noun phrase of “baseball cap.

4. Commas and Essential/Nonessential Clauses:
Use commas to indicate when a word or phrase is not essential to a sentence. In Example 1 below, the phrase "who are elite in their profession" is essential to the meaning of the sentence. Therefore, it isn't set off by commas.

In Example 2, however, the phrase “which consist of players who are elite in their profession” is not needed to understand the meaning of the sentence. Therefore, it is set off by commas.

  • Example 1: Only the players who are elite in their profession are drafted for the all-star games.
  • Example 2: The all-star teams, which consist of players who are elite in their profession, were drafted on Saturday.
Another example of this rule is, “Bill’s dog, Betsy, needs to go to the vet.” The commas indicate that “Betsy” is not needed in the sentence, so Betsy must be Bill’s only dog. If there were no commas, then “Betsy” is essential meaning Bill has multiple dogs and Betsy is the one who needs to go to the vet.

5. Commas With Hometowns and Ages:
Commas are used when a person’s hometown or age is used as an appositive. This is seen in the following sentences:

Samuel Perkins, Kansas City, Mo., finished in first place.
Text Box: Example 3 – Introductory Element: If you intend on going, bring an umbrella. Examples of Transitional Words: -however -nevertheless -well -yes -no -meanwhile -furthermore -still -also -hence -consequently -therefore Sarah Jenkins, 37, was the first on the scene.

6. Commas and Introductory Elements:
One of the most common reasons for a comma, an introductory element is helpful in setting the scene of the sentence. The basic rule is that a comma must be used to set off introductory phrases and clauses. Additionally, a comma is needed when the sentence starts with a transitional word. Omitting the comma confuses the reader and could relay a message far from the intended meaning.

7. Commas and Parenthetical Elements:
AP style discourages the use of parenthetical elements, such as “The writer, regrettably, used a parenthetical element.” Remove any instances of parenthetical elements you come across.

8. Serial Commas:
Serial commas are the bane of writers just starting their career with OneSpace. Do not use serial commas! A serial comma is a comma placed in front of the conjunction between the final two elements in a series (“He has a cat, dog, and bird”). For all OneSpace writing, do not include the serial comma (“He has a cat, dog and bird”) unless it falls under the exception. Serial commas are the most common error that beginner writers make. While they are not article-decimating errors, they are still mistakes that must be fixed by an editor, and a missed serial comma leaves an inconsistency. A trick that makes it easy for you to check your article for serial commas is to do a “find” (CTRL+F) for any possible occurrence of a serial comma. When you have the “find” bar open, search for “, and” and “, or” to remove any serial commas you find.

Text Box: Example 4 – Correct – He plays soccer, baseball and hockey. Incorrect – He plays soccer, baseball, and hockey. Exception – He plays soccer, baseball, and track and field. There is, however, an exception to this rule shown in the example below. When the last element in the series contains a conjunction, a serial comma is used to separate the last two items in the series.

Correct – He plays soccer, baseball and hockey.
Incorrect – He plays soccer, baseball, and hockey.
Exception – He plays soccer, baseball, and track and field.
Track and field” is a single element in the series, so a comma is placed between “baseball” and “track and field.”

While there are numerous rules regarding the usage of commas, using them properly creates consistent content that reads properly. This keeps the reader interested in the writing, allows the reader to trust the integrity of the article and encourages the reader to continue reading.


Apostrophes are used in three cases: to show omission, to show plurals of single letters and to show possession. The first two cases are fairly simple, but possession rules are more complex.

1. Omission:
Contractions are the most common form of apostrophes showing omission. Contractions are allowed in AP style, but contractions should not be used in articles for OneSpace.

An apostrophe can also indicate omitted letters within a word or saying. Rock and roll (rock ‘n’ roll) and until (‘till) are commonly shortened by adding apostrophes. However, do not omit letters unless they are part of a name or title.

You can use an apostrophe to shorten a year if the century is obvious within the context of the content. The 1920s can be shortened to ‘20s, and class of 2006 can be shortened to ’06.

2. Plurals of Single Letters:
An apostrophe is used to indicate the plural form of single letters. For example, “She earned three A’s and two B’s,” and, “Dot your i’s and cross your t’s,” use an apostrophe to show the plural form of the letters. Ensure you do not make the mistake of applying this rule to years. Saying the “1920’s” does not indicate the plural form of “1920.” Rather, it shows that the year possesses something.

3. Showing Possession:
Like with commas, there are many rules for using an apostrophe to show possession. However, these rules are very manageable and easy to learn.

Text Box: Example 5 – Singular common nouns: -Horse’s -State’s Singular common nouns ending in “s”: -Waitress’s Singular proper nouns ending in “s”: -James’ -Jones’ Plural common nouns: -Men’s -Alumni’s Plural common nouns ending in “s”: -Girls’ -States’ Apostrophe rules to make common nouns possessive are basic. However, there are exceptions to these rules. A noun that is both singular and plural, such as deer, requires an apostrophe and “s” regardless of use. If the noun is both singular and plural and ends in an “s,” such as scissors, only use an apostrophe. Other exceptions are common nouns ending in s or with an “s” sound that are followed by a word that starts with an “s”, such as “the waitress’ shifts” or “appearance’ sake.” In these cases, omit the “s” after the apostrophe. Pronouns, such as “anyone’s guess,” and compound words such as “lieutenant governor’s” follow the same basic rules, but descriptive phrases have exceptions. If the descriptive word is plural but does not end in “s” (young men’s group), then use an apostrophe. However, when a word ending with “s” is used descriptively, do not use an apostrophe. This can be seen in, “The style guide serves as a writers cheat sheet.” Determine if a word is descriptive by using the long form of the phrase. If the long form includes “for” or “by,” such as “serves as a cheat sheet for writers,” then it does not use an apostrophe.

When referring to a jointly owned object, use an apostrophe after the last word only, such as “Gary and Linda’s house.” However, if each person lives in a separate house and you are talking about both houses, “Gary’s and Linda’s houses,” then you would use an apostrophe for both.

Singular common nouns: -Horse’s -State’s
Singular common nouns ending in “s”: -Waitress’s
Singular proper nouns ending in “s”: -James’ -Jones’
Plural common nouns: -Men’s -Alumni’s
Plural common nouns ending in “s”: -Girls’ -States’

Do not make inanimate objects possessive. Instead of writing “shingles’ symptoms”, write “the symptoms of shingles.”

Colons and Semicolons

1. Colons:
Text Box: Example 6 – Introducing a sentence: -He swore to his constituents: He is going to change the world. Introducing a list: -Gather the three tools you need for the project: a drill, screws and an Allen wrench. Creating emphasis: -He had one feeling while watching the ball sail over the fence: joy. Colons are used at the end of a sentence when introducing a second sentence, to introduce a list or to create emphasis for the following phrase. Include a colon when a sentence naturally leads into and introduces the following sentence. There are two complete sentences in the example, but the first naturally introduces the second. Only capitalize the word following the colon when it is a proper noun or when it is the start of a complete sentence.

Use a colon when you directly introduce a list. Do not include “such as” or “like” after the colon, and do not use a colon directly after a verb. For example, a colon is not used after “gather” in the following sentence: “You must gather a drill, screws and an Allen wrench.”

Lastly, colons create emphasis for a final word or phrase within a sentence. Colons are useful when you want to boost the meaning or add to the effect of the sentence. As seen in the example, the sentence builds up the feeling and effect of the emotion. The sentence could say, “He felt joy while watching the ball sail over the fence,” but the sentence lacks the feeling and drama of the colon.

2. Semicolons:

Semicolons are used to separate thoughts or information. Their effect falls between commas and periods.

Use a semicolon for two complete sentences that are linked but are separate thoughts, such as “The siege ended after 10 weeks; it was a gruesome and costly battle.” Do not capitalize the first word following the semicolon unless it is a proper noun. Additionally, if a number is used after the semicolon, follow numeral usage guidelines; the number is not always spelled out as if it were the first item following a period.

Semicolons are also used to separate items in a series when the series contains commas. For example, “She is survived by a daughter, Jane Doe, of New York City; two sons, John Doe, of Flint, Mich., Joe Does, of Boston; and a brother, Ken, of Madison, Wis.” However, reconstructing or breaking apart the sentence to minimize punctuation is best.


Hyphens add clarity to sentences and eliminate confusion that readers may experience. They do this by compounding modifiers and clearing up ambiguous or hard-to-read phrases.

Text Box: Example 7 – Compound Modifiers: -A top-tier pitcher -A neon-green cake -A lightning-fast reaction -The cake is neon-green. -His reaction was lightning-fast. Exceptions: 1. A very odd expression 2. A slyly worded poem 1. Compound Modifiers: Use a hyphen to connect two or more words that express a single concept when the compound modifier precedes the noun it is modifying. The words “lightning” and “fast” are compounded to modify the noun. When the compound modifier appears after the noun and directly after a form of the verb “to be,” include the hyphen for added clarity. As an exception, do not include a hyphen when the word “very” is included or when one of the words is an adverb ending in “ly.”

2. Avoiding Ambiguity:

Include a hyphen if the phrase is confusing without it. For example, “a group of small-business men” requires a hyphen. Without the hyphen, the reader may be confused because small could imply stature and “businessmen” is separated into two words. However, the section clearly means “men with small businesses” with the inclusion of the hyphen.

Another way to avoid confusion is by adding a hyphen in a word that contains duplicated vowels and tripled consonants. Words such as “anti-inflammatory” and “bell-like” include a hyphen to allow for easy reading. Additionally, if the first part of the word is a proper noun and the second is “like,” then include a hyphen. For example, “Norwalk-like” includes the hyphen since “Norwalk” is a proper noun.

Suspensive hyphenation clears up content that uses two hyphenated phrases that share a common element. The phrases “short-term investments” and “long-term investments” share a common element and are combined as “short- and long-term investments.” By using suspensive hyphenation, you clear up redundant wording and possible confusion.

There are many rules and guidelines surrounding punctuation usage. However, understanding the rules and situations in which punctuation is required increases your editing speed and reduces the number of errors that slip through to the final copy. As a result, you become a trusted editor with more opportunities, and happy clients continue to request writing work.