Common Comma Usage

Hey, guys! Welcome to this video on comma rules.

Commas tend to get misused a lot, or perhaps even worse, they aren’t used where they should be. So, in this video we are going to take a look at ten different comma rules to be aware of when writing.

Rule #1:

When you have a coordinating conjunction that is being used to separate two independent clauses, use a comma.

For example:

My brother rode his bike so fast, but he still arrived late for school.

Rule #2:

When you have an intro clause, phrase, or just a couple of words that precede the main clause, then use a comma to separate them.

Here’s an example:

When I was younger, I used to roller skate to the neighborhood park with my family.

Rule #3:

When you have a nonrestrictive clause in the middle of a sentence then use a pair of commas to separate it. Nonrestrictive clauses are just clauses that are not essential to the meaning of the sentence.

For Example:

My paper, which I think you might like, is about changing psychological behaviors in our culture.

Rule #4:

Use commas when you have three or more words that are within a series to separate each word.

Here is an example:

The ingredients that I need for you to pick up from the store are onions, potatoes, sour cream, and cheddar cheese.

Rule #5:

When you have multiple adjectives modifying the same noun they need to be separated by commas.

For example:

The strong, lean olympian catapulted herself over the bar.

*Notice, there is no comma after lean. The last adjective right before the noun should not have a comma after it.

Rule #6:

Use commas to separate opposing coordinate words, or to represent a clear pause or change.

For example:

She was simply uninformed, not stupid.

We are still going to the fair together, right?

Rule #7:

Use a comma to distinguish phrases at the start or end of a sentence that are referring to something in the middle or at the beginning of a sentence.

Look at this example:

Sweet Emma yelled, “choo choo,” as the train passed by, jumping enthusiastically.

Rule #8:

Use commas to distinguish geographical names, addresses (except for the first line), format dates (with exception of month and the day), and to set apart a title in someone’s name.


Hollywood, California is where a lot of major films are made.

Her address is 59 Crestview Drive, Layton, Utah.

George C. Oxford, PhD, has written over thirty-seven books on the human brain.

Rule #9:

Use commas to separate the normal flow of writing from quotations.

For example:

The frustrated young student asked, “Why on earth do we exist?”

“You are doing great,” she said, “keep working hard!”

Rule #10:

Use a comma if it helps the sentence to be read correctly, or if a comma would help to eliminate any possible confusion.

Look at this example:

It seemed as though there was never enough encouragement at work, to Martha.

The Oxford Comma

Now, before we close here, let’s talk about one last thing. Let’s take another look at rule #4. Use commas when you have three or more words that are within a series to separate each word.

The example we saw was:

The ingredients that I need for you to pick up from the store are onions, potatoes, sour cream, and cheddar cheese.

Well, the comma immediately following sour cream is referred to as the Oxford comma. The Oxford (or serial) comma can be defined as the comma that comes after the second to last item in a list of three or more items, right before and or or.

The Oxford comma is referred to as stylistic, which means that depending on what type of style you use, it may not be necessary. For example, if you are writing in AP style (which is what news reporters use) then you would not use the Oxford comma.

Typically, you will hear it said that it is up to you to decide if you want to use the Oxford comma or not. However, you want to be very careful, because this can potentially lead to some confusion. I’ll show you how.

I like my friends, Beyonce and Abraham Lincoln.

Now, the problem with this sentence is that it seems as though this person is claiming to be friends with Beyonce and Abraham Lincoln. When, really, what they meant to communicate was that they like their friends, Beyonce, and Abraham Lincoln. So, in any case, when writing make sure that you are communicating effectively what you would like for your audience to take away.

I hope that this video over commas, and how to use them has been helpful for you.

See you guys next time!


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by Mometrix Test Preparation | Last Updated: December 15, 2021