By Cheryl Bolen
When I used to teach English I would tell my students there was
not much they could do to improve achievement (standardized) test
scores in math and reading. They were born with those abilities. But on
the grammar portion of the test, they could do extremely well because
capitalization and punctuation rules could be learned. Indeed, my
students performed above grade level after being in my class for just a
You, too, can profit by learning a few simple rules. Nothing turns
off an editor more than incorrect comma usage because unnecessary or
omitted commas make a manuscript difficult to read.
Did you notice in the above sentence I did not use a comma before
the word because ? That is because because is a
conjunction that joins without a comma.
The following are some simple guidelines for correct comma usage:
Direct Address and Introductory Words
A comma is used to set off a name or expression in a direct
address. Here are some examples:
Dad, I did answer you.
You look pretty, Mom.
Gee, I really don't know.
Yes, I will go.
Commas with Adjectives
Use a comma to separate two or more adjectives preceding a noun.
Dark, threatening clouds gathered.
This is one of the most frequently violated comma rules. A comma
is used to set aside a word or group of words placed beside another word
to rename or explain the noun. Example:
I invited Kim, my best friend, to the party.
My best friend is the appositive describing Kim.
Remember, IF THE REST OF SENTENCE CAN STAND ALONE WITHOUT THE
APPOSITIVE, YOU NEED THE COMMAS.
An appositive can be located anywhere in a sentence. It is always
set off from the rest of the sentence with one or more commas, depending
on the location of the appositive. Examples:
A graphically violent movie, SAVING PRIVATE RYAN has won many
awards. (The appositive here is a graphically violent movie. The
rest of the sentence can stand alone without the appositive.)
We went to see the Transco Tower, the tallest building in Houston.
(The tallest building in Houston is the appositive. The rest of
the sentence can stand alone without the appositive.)
Be sure not to use a comma to set off descriptions which are not
Coach Guy Lewis had the winningest record in UH history. NO COMMA
between Coach and Guy.
Commas with Quotations
Use a comma to set off someone's exact words from the attributive
part of the sentence. Example:
He said, "You can go."
"You can go," he said.
REMEMBER, 99 percent of the time the punctuation is located INSIDE
the quotation marks.
Commas with Compound Sentences
This is another frequently violated comma rule. First, let's
discuss the difference between a complex and a compound sentence. A
compound sentence is when two complete sentences are joined together
with a coordinating conjunction (and, but, or). Example:
John mowed the lawn, and he swept the sidewalk. Both John mowed
the lawn. and He swept the sidewalk. are complete sentences
as they have a subject and a predicate (noun and verb).
Each of these could stand alone as a sentence.
Remember, a compound sentence always needs a comma.
However, the following sentence does not take a comma. Example:
He mowed the lawn and swept the sidewalk. This sentence is
actually a single subject with a compound predicate, and it is NEVER
acceptable to separate a subject from its predicate with a comma.
With Subordinate Clauses and Phrases
Adverbial and participial clauses and phrases that precede a main
clause are usually set off with commas. Examples:
As vehicles age, they depreciate.
In addition, be sure to sign and return.
To comply, you must use your Visa card.
I used to tell my students ing pharases, either before or
after the main phrase are always set off with commas. Examples:
Having painted the exterior, they moved inside.
He picked up the baby, kissing the top of its soft head.
There are two areas of comma usage in which the rules are
ambiguous. The first regards the use of commas in a series. Texas
textbooks and most books teach the use of using a comma before
the word and in a series. Example:
The flag is red, white, and blue.
However, the Associated Press Stylebook and other style manuals
feel the comma before and is redundant.
The other area of ambiguity is in clauses and phrases preceding
the main clause. Examples:
In 1919, his family left Russia.
Journalists always set off this type of phrase with a comma.
Literary stylists, however, do not.
Many other simple phrases can be set off with commas but don't
have to be. I say it's your choice.
A comma rule of my high school English teacher back in the sixties
still works quite well: When in doubt, leave it out.