The Easiest Way to Learn How to Use a Comma


A comma (,) is one of the two most commonly used punctuation marks (along with a period). It is also a source of a lot of frustration for the graders of essays and term papers. Why?

  • A skipped comma may mean that the writer is in a rush
  • A comma used in a wrong way may change the meaning of a sentence (sometimes to the opposite)
  • Using the comma incorrectly multiple times in an essay will make you come across as lazy or incompetent and will drive your grade down
  • Professors and instructors have very little patience for the misuse of the comma – trust me, I know

So, why not spend a couple of minutes and make friends with the comma – hey, if you take care of the comma, the comma will take care of you.  🙂

So, in this blog post, we’ll learn how to stop skipping commas.

You see, a comma is an equivalent of a pause in human speech. Please read the following sentence aloud:

Sports is also considered to be very good physical exercise and when we are physically fit the probability of mental fitness also increases.

Now did you feel something strange as you were reading it? What felt not quite right?

You see, if this were a sentence that someone uttered to you on the street, and it was uttered just the way you just read it, it would feel like this person is in a rush to get somewhere, but just has to say something long and important to you on his way without even stopping to hear your reply. And why does it read that way?

It is because this person hasn’t paused once while uttering this sentence. Read it again (and make sure you read aloud), and you’ll notice it this time.

Please note also that the only thing that saves this sentence from being a run-on sentence is the word ‘and.’ But I’ll show you how to get rid of run-on sentences in a future post. In the mean time, let’s take a closer look at the sentence. It really contains two separate sentences:

Sports is also considered to be very good physical exercise.

When we are physically fit the probability of mental fitness also increases.

Now, to the credit of the writer, I must say that although these two sentences can be written separately, they really belong together because they are parts of the same thought.

So, let’s read the first sentence aloud again:

Sports is also considered to be very good physical exercise.

Did you naturally want to pause anywhere? No – it’s a pretty simple sentence.

Let’s read the second one aloud:

When we are physically fit the probability of mental fitness also increases.

Did you naturally feel a need to pause at any time while reading this one?

Well, I hope you discovered that you did. This part of the sentence – “When we are physically fit” – is called an introductory phrase. This simply means that this phrase makes the person uttering it to pause naturally right after it before continuing with the rest of the sentence.

Try saying it without rushing, and you’ll hear yourself pausing right after the word ‘fit.’ No, really, try it.

Can you hear it? Can you hear yourself pause after saying “When we are physically fit?”

Good. Now, here’s a rule that should be easy to follow now that you understand the connection between a pause in speech and a comma in writing:

Always put a comma after an introductory phrase, because this is the way people speak.

So, let’s get back to the original long sentence:

Sports is also considered to be very good physical exercise and when we are physically fit the probability of mental fitness also increases.

Since we know that we should put a comma after the introductory phrase, let’s do it:

Sports is also considered to be very good physical exercise and when we are physically fit, the probability of mental fitness also increases.

Now that our introductory phrase has become a part of a longer sentence and is preceded by a full sentence as well, it has become a parenthetical expression. You may think of it as simply an introductory phrase that introduces the second part of a longer sentence.

And what does ‘parenthetical‘ mean? It means that this part of the sentence could be included in parentheses but, instead, we simply must place a comma before and after the phrase. So, let’s do that as well:

Sports is also considered to be very good physical exercise and, when we are physically fit, the probability of mental fitness also increases.

So, let’s read the sentence aloud (yes, aloud one more time), this time pausing at every comma. I hope you’ll see the improvement in the way the sentence sounds.

Did you hear the difference this time?

I hope you now see the difference between:

Sports is also considered to be very good physical exercise and when we are physically fit the probability of mental fitness also increases.

And

Sports is also considered to be very good physical exercise and, when we are physically fit, the probability of mental fitness also increases.

So, here’s your takeaway from today’s lesson:

  • A comma in writing is like a pause in speech
  • When writing a long sentence, read it aloud, check it for natural pauses, and place a comma or two, if necessary. Then, read again for proof.
  • If you do this regularly, you’ll develop a sense for using the comma
  • Your sentences will become more elegant and mature, and your grades will go up as a result

Questions? Post one as a comment.

Tutor Phil

Tutor Phil

Tutor Phil is an e-learning professional who helps adult learners finish their degrees by teaching them academic writing skills.

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