Everyone has seen the sentences.
When you eat Maya can clean up.
When you are finished digging the dog can go for a walk.
Hannah got down on her knees, she begged.
Commas add clarity and make it easier to read sentences. When a comma is misplaced or omitted altogether, the resulting sentence is enough to make readers scratch their heads. And if you aren’t looking for confusion and random humor in your writing, it’s best to learn the laws of the comma.
In the age of advanced technology and spell checkers, it’s easy to think that you won’t have to worry about grammar and spelling. You trust your computer to fix it for you.
It’s vital to clear up this misconception straight away. Spell checkers do catch some of your missed or overused commas, but only around 2/10 mistakes will be flagged in all your writing.
A common example of spell checkers going awry is auto-correct. Think about all the times your auto-correct has thought you’ve spelled something crazy when you meant something normal. Technology is an enemy cleverly disguised when it comes to grammar, especially with those tricky commas. Instead of relying on grammar checkers constantly, have the comma laws up your sleeve and ready for anything.
The Golden Rule
Commas, one of the most used forms of punctuation (the first is the period), are commonly overused and misused. You learn about them in school, think you have the hang of them, then start placing them all willy-nilly into every document you write. This is not the correct approach. Over time, school lessons about the comma fade and become jumbled up with rules about semicolons, dashes, and ellipses marks.
To ensure you are using commas where and when you need to, there are two rules (two half-rules really) that make up one Golden Rule. The first half is always this: listen for the pause in the sentence.
The best way to discover where commas go in a sentence is to read your document aloud. Are there any sentences that you lose breath reading? Try putting in a comma to break them up. Are there sentences that have too many pauses; therefore, becoming overly confusing? You can take out some commas as long as you don’t alter the meaning of the sentence.
The second half of the Golden Rule is that you should rarely, unless it is a special circumstance, separate a subject from its verb. Watch out for long and complex subjects, for they cause lots of problems with the Golden Rule.
Rule #1: Use a Comma with Dependent Clauses and Introductory Words
Words and phrases that begin a sentence are usually separated from the rest of the sentence to promote clarity and avoid misreading. An introductory phrase is also called a dependent clause.
A dependent clause is a sentence that cannot stand on its own. It requires a second sentence to support it because it only has a subject and verb but doesn’t express a complete thought. If you have a dependent clause, use a comma to set it off from the rest of the sentence.
When David gets here, give him the platter of cookies.
If you write a sentence with a dependent clause, in most cases you will use a comma. There are, however, a few circumstances where using one is optional. The first is if you have a three- or four-word phrase that is easily understood.
Once we found it she screamed with glee.
This also applies to sentences that begin with a preposition. A preposition is a word that tells you the location of something in comparison to something else. If the preposition is four words or less, the comma is optional.
Upon the silky cushion he sat.
However, if a dependent clause starting with a preposition contains more than one preposition, you should use a comma. The only exception is if a verb follows directly after the clause ends.
Across the lake and down the hill, the hidden baseball field sits.
Across the lake and down the hill sits the hidden baseball field.
If a sentence begins with an introductory word like namely, i.e., e.g., or for instance and is directly followed by a series of items, a comma can be placed before and after that word, respectively.
There are many options for exercise at the Newfort Gym, namely, running, swimming, and cycling.
Rule #2: Use a Comma with Conjunctions
Confusion presents itself when it comes to commas and conjunctions. Everyone uses conjunctions in their writing. They are the words and, but, or, so, for, nor, and yet. The problem with commas and conjunctions is writers tend to misunderstand where the two should go hand-in-hand.
Commas should precede conjunctions only when the sentences on either side of them are independent. An independent sentence has a subject, verb, and complete thought.
He drove his car to the shop, and he discovered the oil needed changing.
You can omit the comma in sentences that are short and clear.
I run and she skips.
The other exception to this rule is when the subject in the second sentence doesn’t appear before the verb. Only add a comma if the doer of the action is confusing.
The bear growled ferociously and reared up on his hind legs. (The bear does both actions.)
The man cowered as the bear growled ferociously, and cried. (The man cries in this sentence, not the bear, hence the comma.)
Rule #3: Use a Comma to Separate Words or Word Groups in a List
In lists, commas should be used to separate words, word groups, or phrases. Only use a comma if there are more than two words in a list.
On the pizza, include peppers, mushrooms, and olives.
That last comma after the word “mushrooms” is called an Oxford or Serial comma. This comma is used commonly in fiction and other writing in Canada and the US. It is typically not used in newspapers and magazines. You can choose to use it or omit it but be consistent.
However, it must always be used in cases where there is cause for confusion.
Please pack the ice cream, peanut butter and jelly and granola bars. (In this sentence, peanut butter and jelly are grouped together while the rest of the food is not. To show that they are one, add a Serial comma.)
Please pack the ice cream, peanut butter and jelly, and granola bars.
Rule #4: Use a Comma to Separate Coordinate Adjectives
Commas should be used to separate two coordinate adjectives. Coordinate adjectives modify the same noun and can be reversed or interchanged.
The small, scared dog ran underneath the shed.
To determine if you have coordinate adjectives or not, try swapping them to see if the sentence still makes sense. Also, you can put the word “and” between them.
The scared, small dog ran underneath the shed.
The small and scared dog ran underneath the shed.
Rule #5: Use a Comma to Set Off Non-restrictive Items
Some sentences include information that is not essential to the meaning of the sentence. This is considered non-restrictive information. Commas should set off all non-restrictive words, clauses, and phrases. If the non-restrictive information appears mid-sentence, remember to use an appositive comma. An appositive comma is a comma that closes the clause or phrase.
The cat, that is black, jumped onto the sofa.
The four sisters, Luna, Mary, Susan, and Brittany, were tanning on the beach.
Don’t include commas if there is no identified subject in the sentence.
The man with a bald head walked past the hairdresser.
Rule #6: Use a Comma with Direct Quotations
When you use dialogue or a direct quote in your writing, more times than not, it needs to be started or ended with a comma. And the comma needs to be inside of the quotation marks, not outside.
“Today I went to the park,” said Sally.
There are a few exceptions to this rule and they all depend on the format of the sentence. If you have a one-word quotation, the comma can be omitted unless the quotation is followed by a dialogue tag.
Diane yelled “Stop!”
“Stop,” Diane said.
In rare cases, a direct quotation can be the subject or object of the sentence. In this situation, using a comma is optional.
Is “how are you” all you can say to me?
Rule #7: Use a Comma with But and And
Only use a comma before the word “but” if it joins two independent clauses.
Burgers taste delicious, but pizza tastes spectacular.
The same rule applies to the word “and” and commas. Never put a comma before the word “and” if it’s a list of only two items.
Sarah ate her breakfast, and she went out for a walk.
Rule #8: Use a Comma with Names
When directly addressing names, nicknames, terms of endearment, or the title of a person, make sure you set them off with a comma or two.
How are you today, James?
Thank you, Doctor, for telling me.
Baby, you look great!
Rule #9: Use a Comma with Dates
If you include a date in a sentence, commas are required. However, proceed with caution placing the commas because each date format has different rules.
If you write the full date, separate the day of the month and the year with a comma and put a comma after the year.
On October 31, 2008, we had the best Halloween party.
If you write only the month and year or format the date to day-month-year, no comma is required.
I learned how to draw in April 2003.
If your date includes the day of the week as well as the date, separate the day and date with a comma.
On Friday, April 13, I won’t go outside for fear of bad luck.
Rule #10: Use a Comma with Places
When writing a city and its state or country into a sentence, a comma should be used to separate the city and state/country. Also, add one after the state/country to set it off from the rest of the sentence.
I’m going to London, England, in a week.
Rule #11: Use a Comma After Certain Words and Expressions
Some written dialogue will begin with a word such as well, yes, no, hello, or why. Of course, you can use these words in a regular sentence, but you must follow them up with a comma in all situations. If these words are in the middle of a sentence, separate them with commas on both sides.
“Well, I guess I will come.”
I don’t like that, no, I don’t.
Also, use this rule with expressions and words that interrupt the flow of a sentence such as nevertheless, however, after all, by the way, and certainly.
I am, however, terrified.
Rule #12: Use a Comma with Parentheses
Sometimes, information is included in parentheses in the middle of a sentence. Parentheses are used to add in an afterthought or piece of information that is not essential enough to be added with a dash. When putting commas in a sentence with parentheses, the commas should never be placed inside of parentheses. They should only be on the outside and only if there is a need for commas in the main sentence.
After the gun went off, Delilah peeked up and out of the bushes.
After the gun went off (it was a delightful sound), Delilah peeked up and out of the bushes.
Run-on sentences are a writer and reader’s worst enemy. They are choppy, disorganized, and at times, even confusing. Sadly, they are a common error. Many writers, from a habit formed by misunderstood comma rules, put commas in between two independent clauses rather than the proper punctuation they require.
At the beginning of this article, I listed an example of a comma splice:
Hannah got down on her knees, she begged.
This sentence contains a comma splice. A comma splice is a fancy term for a misused or lost comma. It doesn’t belong in a sentence. Take it out and replace it with the correct punctuation or split the sentence.
If you want to keep the sentence intact, you can add a conjunction or semicolon between the two independent clauses.
Hannah got down on her knees, and she begged.
Hannah got down on her knees; she begged.
If you are willing to, split the sentence into two separate sentences.
Hannah got down on her knees. She begged.
“Do Not” Comma Rules
As previously mentioned, commas have a way of finding their way, in abundance, into our writing. We may think that a comma is needed when the writing will thank us for leaving it out. To ensure you are not adding unnecessary and possibly confusing commas in your writing, glance over these important “Do Not” comma rules.
If a sentence begins with an independent clause and is followed by a dependent clause, do not put a comma between them.
Don’t do this: Tell me now, if you want to come.
Do This: Tell me now if you want to come.
Never, ever separate a verb from its direct object. A direct object is what the verb is acting onto.
Don’t do this: The girl hit, her brother.
Do this: The girl hit her brother.
Articles (a, an, the) and nouns should never be separated from each other. Treat them like conjoined twins.
Don’t do this: She would like an, umbrella, so she won’t get wet from the rain.
Do this: She would like an umbrella, so she won’t get wet from the rain.
Don’t put a comma between an adjective and its adverb. This is a common mistake because coordinate adjectives require a comma between them. However, even in that situation, the comma doesn’t go between the adjective and the word it is describing.
Don’t do this: The adoringly, happy kids watched the musician play.
Do this: The adoringly happy kids watched the musician play.
When you have correlative conjunctions in your sentences, don’t separate them with a comma. Examples of correlative conjunctions are either/or, neither/nor, not only/but also, and both/and.
Don’t do this: Neither the steak, or the chicken was cooked all the way through.
Do this: Neither the steak or the chicken was cooked all the way through.
When it comes to the phrase “as well as”, only surround it with commas when it is part of a non-restrictive clause.
Don’t do this: Pick up your clothing, as well as, the groceries when you go out.
Do this: Pick up your clothing as well as the groceries when you go out.
Unless: Toes, as well as fingers, should be of equal number.
As with “as well as”, don’t use commas with the phrase “such as” unless it is part of a non-restrictive clause.
Don’t do this: Animals, such as, raccoons and owls are nocturnal.
Do this: Animals such as raccoons and owls are nocturnal.
Unless: Nocturnal animals, such as raccoons and owls, come out after midnight.
Don’t use commas to separate two nouns that are paired together by a compound subject or object.
Don’t do this: The dog, and the cat walked down the road. They were both wearing red collars, and blue hats.
Do this: The dog and the cat walked down the road. They were both wearing red collars and blue hats.
If your sentence has a compound predicate, don’t use a comma. A compound predicate is the part of the sentence that contains a verb and subject, only there are two verbs and they share one subject. Only use a comma when you think the sentence is capable of being misread.
Don’t do this: My dad sang, and danced. He wanted to play his fiddle too, but left it at home.
Do this: My dad sang and danced. He wanted to play his fiddle too but left it at home.
Unless: My dad yelled at a woman in the audience who booed, and left. (The dad left, not the woman.)
When a phrase begins an inverted sentence, don’t put a comma after it. An inverted sentence has a subject that follows a verb, instead of the other way around.
Don’t do this: Above all the houses, flies the kite that was taken from my hand.
Do this: Above all the houses flies the kite that was taken from my hand.
In a series of items, don’t put a comma before the first or last item.
Don’t do this: She felt nervous, excited, and ready, for the test.
Do this: She felt nervous, excited, and ready for the test.
Don’t do this: Extreme alcohol consumption can cause, car accidents, sickness, and stupidity.
Do this: Extreme alcohol consumption can cause car accidents, sickness, and stupidity.
Next time you are unsure about a comma, try to avoid relying solely on spell checkers. Learn these rules and become a master of the comma so that Deputy Grammar doesn’t come knocking at your door because someone has eaten Maya or dug the dog.