What is incorrect use of a comma?

Plenty of grammar books highlight the rules for correct use of commas, so I don’t intend to repeat that information.

I have found, however, that a quick reminder on where or when not to use commas is often helpful.

Commas are used to separate words and phrases into chunks of information that make sense to the reader. Correct use of commas allows the reader to take in the information without pause. Incorrect use of commas can cause confusion or even a misreading of the information.

In fiction, misuse of commas may create humor where none was intended or cause the reader to stop and have to reread for clarity. Each time a reader stops because of confusion, he is pulled out of the fiction that the writer worked so carefully to create.

So… When shouldn’t you use a comma?

~ Don’t use commas to separate two subjects [a compound subject] doing the same thing

Billy and Buster wanted burgers for dinner.

She and her cat were thrown from the spinning ride.

Hoping to become famous, Liza and Burt ran to the newspaper office.

Incorrect: Billy, and Buster wanted burgers for dinner. X
She, and her cat were thrown from the spinning ride. X
Hoping to become famous, Liza, and Burt ran to the newspaper office. X

Note, however, the comma for more than two subjects: Sally, her mom, her sister Arnelle, and the conductor held a screaming match at the border crossing.

~ Don’t use commas to separate two actions of a subject [simple or compound]

Tootie drank the moonshine and passed out.

Elmer and Emerson walked to the grocery store and bought Scooter Pies.

Happy with their winnings, Patricia and Robert made plans to buy a new house and torched the old family home.

Incorrect: Tootie drank the moonshine, and passed out. X
Elmer and Emerson walked to the grocery store, and bought Scooter Pies. X
Happy with their winnings, Patricia and Robert made plans to buy a new house, and torched the old family home. X

~ Don’t use commas to separate two independent clauses if there is no conjunction between them [this is a comma splice]

Butter tasted good on bread, so Matthew spread it from edge to edge.

Hope is a life saver, but James had used up all of his two years earlier.

Incorrect: Butter tasted good on bread, Matthew spread it from edge to edge. X
Hope is a life saver, James had used up all of his two years earlier. X

Correct a comma splice by using a conjunction and a comma—
Butter tasted good on bread, so Matthew spread it from edge to edge.

by changing the comma to a semi-colon [with no conjunction]—
Butter tasted good on bread; Matthew spread it from edge to edge.

by changing the comma to a period or dash if you want a strong break between the independent clauses—
Butter tasted good on bread. Matthew spread it from edge to edge.

or by changing one of the independent clauses to a dependent clause—
Since butter tasted good on bread, Matthew spread it from edge to edge.

Two exceptions: For short sentences where the independent clauses are closely related, a comma splice may be acceptable. Also accepted under these conditions is the joining of two independent clauses with a conjunction but no comma.

Annie sneezed, Tommy coughed.
Annie sneezed and Tommy coughed.

~ Don’t use commas to separate the subject from the predicate

Richard was happy to win the award.

The red bus careened toward the crowd at the bus stop.

Stuffed into Glen’s pocket were his prized marbles. [no comma, even when the predicate comes before the subject]

Incorrect: Richard, was happy to win the award. X
The red bus, careened toward the crowd at the bus stop. X
Stuffed into Glen’s pocket, were his prized marbles. X

Note, however, the correct comma placement here: The red bus, wildly veering from one side of the road to the other, headed toward the crowd at the bus stop.

~ Don’t use commas to separate the action [verb] of the predicate from the rest of the predicate

What Belle wanted to do was save the beast.

The most important thing to remember is that I love you.

Incorrect: What Belle wanted to do was, save the beast. X
The most important thing to remember is, that I love you. X

~ Don’t use commas before the first or after the last item in a series

We ate steak, lobster, chicken, and candy bars for breakfast.

Morgan, Pat, and John ran for their cars at the news.

Incorrect: We ate, steak, lobster, chicken, and candy bars for breakfast. X
Morgan, Pat, and John, ran for their cars at the news. X

~ Don’t use commas to separate restrictive clauses from the rest of the sentence

The toy that he wanted was out of stock.

I was sad because the girl who lost was my cousin.

Incorrect: The toy, that he wanted, was out of stock. X
I was sad because the girl, who lost, was my cousin. X *

*This last one is tricky. If I’m identifying my cousin as the girl who lost, there are no commas setting off the words who lost. The girl who lost answers the question who is my cousin. She is not only the girl, but the only girl who lost.

If, however, the answer to the question who is my cousin is simply the girl, then you would separate who lost from the rest of the sentence with commas. The words who lost are then a non-restrictive clause. They provide more information about the girl, but they don’t serve to identify the girl, since there’s apparently only one girl.

Now we have two valid sentences but with different meanings. The first identifies the girl who lost as my cousin.  The second identifies only the girl as my cousin.

I was sad because the girl who lost was my cousin.

I was sad because the girl, who lost, was my cousin.

~Don’t use commas to separate a dependent clause from an independent clause when the independent clause comes first

She was despondent because her favorite horse lost.

He intended to go everywhere with her as long as her father didn’t find out.

Incorrect: She was despondent, because her favorite horse lost. X
He intended to go everywhere with her, as long as her father didn’t find out. X

Note correct comma usage when the dependent clause comes first:

Because her favorite horse lost, she was despondent.
As long as her father didn’t find out, he intended to go everywhere with her.

There’s much more to know about dependent clauses and commas. See the article Commas with Subordinate Clauses for more tips.

~ Don’t use commas to separate two nouns or noun phrases in a compound object

Tension mounted when the hit man fingered the rifle and the pistol.

The Pinkertons feared that their quarry was long gone and that they’d never find him.

Incorrect: Tension mounted when the hit man fingered the rifle, and the pistol. X
The Pinkertons feared that their quarry was long gone, and that they’d never find him. X

~ Don’t use commas to separate items in a series when you use a conjunction between each element in the series

I wanted to find him and confront him and beat some sense into him.

Needing more than a job in a drugstore, Miranda planned to study anatomy and physics and botany.

He hoped it wasn’t April or Summer or Penelope banging at his door.

Incorrect: I wanted to find him, and confront him, and beat some sense into him. X
Needing more than a job in a drugstore, Miranda planned to study anatomy, and physics, and botany. X
He hoped it wasn’t April, or Summer, or Penelope banging at his door. X

~ Don’t use commas to separate adjectives from the words they modify

Michael loved his squishy teddy bear.

The bright, beautiful star drew everyone’s attention when night fell.

Incorrect: Michael loved his squishy, teddy bear. X
The bright, beautiful, star drew everyone’s attention when night fell. X

~ Don’t use commas to separate non-coordinate adjectives [adjectives are coordinate (equal) if they can be used in a different order and still make sense and if the sentence makes sense with an and between the adjectives—see the article Keeping Adjectives in Line for specifics]

The two old women wore house slippers and robes to the grocery store.

The love of money is a tragic social problem.

Incorrect: The two, old women wore house slippers and robes to the grocery store. X
The love of money is a tragic, social problem. X

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Breaking the rules of comma usage is acceptable in order to avoid confusion—Lysette turned to challenge the intruder who fell through the window and fainted. If Lysette and not the intruder fainted, add a comma. Lysette turned to challenge the intruder who fell through the window, and fainted. Of course, you could always rewrite the sentence to avoid ambiguity.

There are plenty of rules for when to use and when not to use commas. When you stick to the rules, your readers will be able to follow your meaning and you won’t give them a reason to be pulled from your fiction and your imaginary world. And that’s always a positive, keeping the fiction and not the mechanics in the forefront of the reader’s mind.

Yet, as is true with any rule of writing, the rules on comma usage can be broken if doing so serves the sentence, the scene, or the story. Know the reason for using or not using commas, but use them as you see fit to add style and nuance to your writing.

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Tags: commas     Posted in: Grammar & Punctuation

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