Are you ever writing a sentence and realize that you aren’t sure why you have to write it a specific way? Maybe, you’re proofreading your paper and come across a punctuation mark, and you’re not sure if, or why, that’s what goes there.
General Comma Functions
A comma is a punctuation mark used to separate words, ideas, and phrases. A punctuation mark is a symbol or sign used to direct the reader’s understanding of a sentence. For example, we use periods to mark the end of a sentence, exclamation points to show excitement, and question marks to show that the sentence should be read as a question.
Commas function as a sort of pause between parts of a sentence rather than as an end or as a question. Commas are usually placed in the sentence where you would most naturally take a breath if you were reading the sentence aloud. We also use commas to add emphasis to our writing, to make the reader pause and think about what is being read, and to allow for more information to be said in the clearest way possible.
Today, we’ll look at how and why you should use commas.
Direct Address
In writing and speech, we use commas when giving a direct address to someone. A direct address is simply when you are directing your sentence to a specific person. For this reason, a comma must come either immediately before or after the address is made. Placement of the comma will just depend on when the address is made in the sentence.
Let’s look at a couple of examples:
Example 1
In this example, you would place your comma after the word Mom to add clarity to the sentence and to specify that it is Mom you are speaking to.
Example 2
If we change the structure of the sentence, it might look something like this:
In this one, the comma comes directly before Mom. By placing the comma before Mom, you are showing that the question is directed toward Mom rather than someone else.
Example 3
Here’s a third way you could use commas for a direct address in your sentence:
In each of these examples, a comma is used to show that the question is directed to Mom. If you didn’t use your comma(s), it would be confusing as to whom your sentence was directed. This is an example of using commas for clarity in your writing.
Dates
You should also use a comma when writing dates. When writing the month, day, and year in the middle of a sentence, you will use commas to separate each piece of information.
Example 1
You need to use a comma when writing your date because without one, your sentence becomes too congested with numbers and words, and it becomes more difficult to read. Using commas when writing the date also allows for interrupting information to be seamlessly included in the middle of a sentence without disrupting its flow.
Example 2
As I’m sure you’re learning, the English language has many exceptions to its rules, such as this next one. If you are writing the date with just the month and the year, do NOT use a comma to separate the month and year. Additionally, you will NOT use a comma after the year.
In this example, it would disrupt the flow of the sentence to include a comma and force a pause where one is not necessary.
Locations
When writing locations, a comma should be used to separate cities from states and to separate cities from countries. A comma is used at this time to show that the city is part of something larger, a state or country. Additionally, commas are used to separate counties and states as well as countries and continents. Let’s look at some examples:
Example 1
In this example, we used a comma to separate a city from a state.
Example 2
In this example, we use a comma to separate a city from a country and to separate a city, state, and country.
Example 3
Here, a comma is used to separate a county and a state.
Example 4
Lastly, we use a comma to separate a country from a continent.
Separating List Items
Another time you’ll want to use a comma is when you’re writing and using a listing method to describe certain objects or situations. When this happens, you’ll want to use commas to separate items in your list. By separating items in a list with a comma, your sentence(s) can be read clearly, and you won’t become tongue-tied when reading. Here’s an example:
In this example, commas are nonexistent. When you begin to write your sentence and you want to include a list, be sure to go in and add your commas. Let’s see what that looks like:
Wow, that looks so much better, don’t you think? By using commas in your lists, each item is perfectly distinguished from the next. Each time you write a list of three or more things, you’ll want to include your commas so as to maintain the flow of the sentence.
Connecting Independent Clauses
You’ll want to use a comma when adding a conjunction (and, if, or, but, yet, etc.) to combine two independent clauses. An independent clause is a sentence that can stand alone, meaning the sentence contains at least one subject and verb in agreement. In the case that you are wanting to combine two complete sentences, use a comma and a conjunction to get the job done! Here’s an example sentence:
Here are two independent clauses, both containing subjects and verbs. Combining these sentences with a comma and conjunction relieves you of having to keep writing short, little descriptive sentences. By combining the two, you are adding variety to your writing. Writing with a variety of sentence styles is a great way to keep your reader interested and keep your work interesting!
Let’s try rewriting those sentences with a comma and a conjunction instead:
That looks so much better! We were able to combine two independent clauses, both having subjects and verbs, just by adding a comma and a conjunction. Now our sentences will read smoothly rather than being choppy like they were before.
Separating Certain Adjectives
Lastly, a comma should be used between two adjectives of the same weight, describing the same noun. This just means that if you’re using two adjectives that roughly convey similar meanings, belong to the same category of description, and can be swapped in the sentence without changing the meaning, you should use a comma.
Let’s work through some examples, together.
Example 1
In this example, ripe and grown are saying similar things about the fruit that Mom buys. One way to test whether or not the adjectives need a comma is to place the word and between them and switch their placements.
Mom only buys grown and ripe fruit at the grocery store.
The meaning of the sentence does not change no matter which way you write it. For this reason, you should place a comma between ripe and grown. If the adjectives do not describe the noun in the same weight, then a comma is not necessary.
Example 2
Here, you would NOT need a comma between large and old. The two adjectives, size and age describe different qualities of the bread that was bought. Because they are different descriptors, a comma would not be used.
Remember, we use commas to add a pause to our sentences in order to make them clearer for the reader. When we have a lot of information to include in our writing, it’s important to make it as easy as possible to keep up with.
These are just a few instances in which you should be using a comma, and with enough practice, you’ll get the hang of them!
Frequently Asked Questions
Q
What is a comma splice?
A
A comma splice is when two independent clauses are joined by a comma. This is something that should be avoided; two independent clauses should be joined by a semicolon or a comma and conjunction instead.
Here’s an example of a comma splice:
“Tori let me borrow her textbook, I needed it to finish my science homework.”
In this case, replacing the comma with a semicolon would fix the comma splice:
“Tori let me borrow her textbook; I needed it to finish my science homework.”
You could also separate the two independent clauses:
“Tori let me borrow her textbook. I needed it to finish my science homework.”
Q
What is an Oxford comma?
A
Also known as a serial comma, an Oxford comma is the final comma used in a list of items, always preceding a conjunction. In the example below, the comma used between flour and the conjunction and is an Oxford comma:
“Jacob bought eggs, flour, and sugar to use in his cake mix.”
Q
Does the comma go before or after “but”?
A
When joining two independent clauses, the comma will always appear before the word but. Here’s an example:
“I wanted to visit the park today, but I can’t find my umbrella.”
When an independent clause and a dependent clause, no comma is needed before or after the conjunction but. Here’s an example:
“She bought some oranges but forgot to buy apples.”
Q
When do you use a comma before “and”?
A
There are two common instances where you would use a comma before the word and. The first instance is when you are joining two independent clauses, as seen in the example below:
“Sarah threw the ball across the yard, and the dog chased after it.”
The other instance is known as the Oxford comma, or serial comma. An Oxford comma is the final comma used in a list of items, always preceding a conjunction:
“I saw lions, giraffes, and snakes at the zoo today.”
Q
Where does the comma go in an address?
A
If you are writing an address on an envelope, a comma should only appear between the city and state. Here’s an example:
John Smith
1234 Example Drive
Atlanta, GA 30311
Notice that there is no comma between the state and the zip code.
If you are writing an address as part of a sentence, a comma should appear between the street and the city, and another comma should appear between the city and state. Here’s an example:
“Marie Johnson lives at 5678 Pretend Avenue, Nampa, ID 83653.”
