fix comma mistakes

Correct Comma Mistakes by Learning These 5 Rules

Grammar can have a huge impact on how something is understood or misunderstood. Comma placement can thoroughly alter the meaning of a sentence. But most of us struggle to know where exactly to put them. How do you decide? Do you consider commas like salt, sprinkling them over your writing according to your personal taste? Have you an indistinct sense that, like too much salt, too many commas are bad for you? Or are you a believer of the ‘breathing’ rule, inserting commas wherever a reader might need an O2 break? Have you ever wondered why those editing your work have to get rid of one comma but not another?

What Is a Comma?

As elaborated by the Oxford Dictionary (2017), a comma “marks a slight break between special parts of a sentence. Used properly, commas make the meaning of sentences obvious by grouping and separating words, phrases, and clauses.” However, commas are frequently a misunderstood grammatical element. Most of the people do not know how to use them properly, and regularly just place them around without paying attention to grammar rules. As they say, commas have the power of saving lives. The placement of a comma in a sentence can, in fact, change its entire meaning. Let’s look at the following example:

The defendant, who looked apologetic, was found guilty.

The defendant who looked apologetic was found guilty.

If we come across at the first sentence the main message we take away is that the defendant was found guilty. In this case, we observe the non-restrictive relative clause “who looked apologetic” between commas. This indicates that the reality he looked apologetic did not change the sentence, it was just a piece of information. However, in the second example, the same clause shows up without commas, thus making the information “who looked apologetic” essential to the meaning of the sentence. Now it seems like there were two defendants, and it was the one who looked apologetic who was found guilty whereas the other walked away free.

While the above statements may only confuse someone reading about the outcome of a case, best practices for grammar rules exist to help prevent uncertainty during any situation that could result from improper punctuation and sentence structure.

Know the rules

The main purpose of a comma is to separate clauses within a sentence, phrases within a clause or words within a phrase, in order to succinctly and unambiguously express meaning. Seems straightforward, right? Wrong. The comma is debatably the most misunderstood of punctuation tools. inquire someone about comma rules and even those who begin with confidence are likely to trail off apologetically. This is because comma use is not entirely explained by rules; it depends in part on taste. It turns out that there are two broad schools of punctuation, and understanding them can help us to unknot the complexities of comma use. In the elocution school, with its roots in antiquity, commas indicate intonation and pauses in oral speech. In the grammatical school, which arose with the initiation of the printing press, commas express grammatical relations among parts of the sentence. What’s complicated is that both approaches are still alive and well, so that most of us have been trained, explicitly or implicitly, to use a bit of both in our writing. Though there are a number of rules to define comma uses, I am defining five basic rules to avoid everyday mistakes:

  1. When the subject and its verb are sides by side, never divide them with a comma.

Incorrect: Fourth-year students and first-year residents, participated in the study.

Correct: Fourth-year students and first-year residents participated in the study.

If you are leaning to place a comma between your subject and verb, this usually signals that your subject is too long and the sentence should be reworked to shorten it. Inserting an elocutionary comma in this case, that creates a pause so the reader can absorb the long subject and note the coming verb is incorrect.

  1. In a compound sentence, a comma is essential before the conjunction that joins the two independent clauses.

Incorrect: The faculty agreed to participate in the new scheme but they were not enthusiastic about its chances of success.

Correct: The faculty agreed to participate in the new scheme, but they were not enthusiastic about its chances of success.

  1. In compound sentences that employ a conjunctive adverb, a semi-colon should precede the adverb and a comma follow it:

Incorrect: The faculty agreed to participate in the new project, however, they were not enthusiastic about its chances of success.

Incorrect: The faculty agreed to participate in the new project, however, they were not enthusiastic about its chances of success.

Correct: The faculty agreed to participate in the new project; however, they were not enthusiastic about its chances of success.

  1. A comma is essential between the main clause and subordinate clause in a complex sentence, regardless of which clause comes first:

Incorrect: Although the new patient record is not believed to influence medical teaching there has been no systematic study of its educational effects.

Correct: Although the new patient record is not believed to influence medical teaching, there has been no systematic study of its educational effects.

Correct: There has been no systematic study of the new patient record’s educational effects, although it is not believed to influence medical teaching.

  1. With relative clauses, a comma signals that the detail is parenthetical, while no comma indicates that the detail is necessary to the meaning of the sentence.

Parenthetical: The staff, who had been carefully trained, were expert customer relation managers.

Necessary: The staff who had been carefully trained were expert customer relation managers.

In the parenthetical version, all staff had been carefully trained and all were expert customer relation managers. You can picture replacing the commas with brackets in this version. In the necessary, or ‘restrictive relative’ version, only the staff who had been carefully trained were expert customer relation managers; the implication is that other staff who were not carefully trained were not expert customer relation managers.

Mistakes to avoid

Now that you are aware of the uses of a comma there are certain errors keep popping up. Here are a few of them.

Identification Crisis

If I’ve noticed it once, I’ve noticed it a thousand times. As referred to a writing, a sentence like:

I went to see the movie, “Midnight in Paris” with my friend, Bob.

Comma following “movie,” comma after “friend” and, sometimes, comma after “Paris” as well. Not a bit are correct — unless “Midnight in Paris” is the only movie in the world and Bob is the writer’s only friend. Otherwise, the punctuation should be:

I went to see the movie “Midnight in Paris” with my friend Bob.

If that appears wrong or weird or anything short of clearly right, bear with me a minute and take a look at another correct sentence:

I went to see Woody Allen’s latest movie, “Midnight in Paris,” with my oldest friend, Bob.

You need a comma after “movie” because this and solitary this is Mr Allen’s newest movie in theatres, and before “Bob” because he and only he is the writer’s oldest friend.

The syntactical situation I’m discussing is identifier-name. The basic thought is that if the name (in the above example, “Bob”) is the only thing in the world described by the identifier (“my oldest friend”), use a comma earlier than the name (and after it as well, unless you’ve come to the end of the sentence). If not, don’t use any commas.

The mystery of the Missing Comma

A related subject is the epidemic of missing commas after parenthetical phrases or appositives that is, self-enclosed content that’s within a sentence, but not vital to its meaning. The following sentences all lack a compulsory comma. Can you spot where?

He was born in Des Moines, Iowa in 1984.

Philip Goth, author of “Portnoy’s Complaint” and many other books is a perennial contender for the Nobel Prize.

If you thought “working,” “Iowa” and “books,” give yourself full marks. I’m not certain why this particular mistake is so tempting. It may sometimes be since these phrases are so long that by the time we get to the end of them, we’ve forgotten about the first comma.

Splice Girls, and Boys
This expression used for the connecting of two independent clauses that are, grammatical units that include a subject and a verb and could stand alone as sentences with a comma.

Here’s an example:

She used to be a moderate, now he’s a card-carrying Tea Partier.

It’s simple to fix in any number of ways:

She used to be a moderate. Now he’s a card-carrying Tea Partier.

She used to be a moderate; now he’s a card-carrying Tea Partier.

She used to be a moderate, but now he’s a card-carrying Tea Partier.

She used to be a moderate — now he’s a card-carrying Tea Partier.

How to decide among them? By reading aloud simply, the best single piece of writing advice and deciding the version that best suits the context, your style and your ear. I would prefer the semicolon. How about you?


 Commas assist your reader to figure out which words go together in a sentence and which parts of your sentences are most important. Using commas incorrectly possibly will confuse the reader, signal ignorance of writing rules, or indicate carelessness. Even though using commas correctly may seem mysterious, it can be easy if you pursue a few guidelines. Whenever you’re in doubt about a rule, take a brief instant to look it up. You’ll save yourself some embarrassment, and you’ll illustrate your readers that you respect language and revere the art of writing well.  There are times and reasons to shatter some of the rules of grammar, but it is wiser to break them knowing what they are and why you should drift.

Beware of trendy myths of comma usage:

MYTH: Long sentences require a comma. A really long sentence may be absolutely correct without commas. The length of a sentence does not decide whether you need a comma.

MYTH: You supposed to add a comma wherever you pause. Where you pause or breathe in a sentence does not consistently indicate where a comma belongs. Unlike readers pause or breathe in different places.

MYTH: Commas are so mysterious that it’s impossible to outline where they belong! Some rules are flexible, but the majority of the time, commas belongs in very predictable places. You can learn to identify many of those places using the tips in this article.

You almost certainly already know at least one of the following guidelines and just have to practice the others. These guidelines are basically all you need to know; if you become skilled at them once, you’re set for most situations.


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