How People Use Commas Incorrectly in English (and How to Get Them Right)
Commas are one of the most commonly used punctuation marks in English, but they’re also one of the most misunderstood. You’ve probably come across sentences where the placement—or lack thereof—of commas has left you scratching your head. Whether it's a misplaced pause, an unnecessary comma, or just confusion over when to use them, comma mistakes can obscure meaning, break up the flow of writing, and sometimes even cause misunderstandings.
In this post, we’ll look at the most common ways people misuse commas and how you can avoid these mistakes to write more clearly and correctly.
1. The Comma Splice
One of the most frequent and serious comma mistakes is the comma splice. This happens when two independent clauses (complete sentences) are joined together by just a comma, without a coordinating conjunction (like "and," "but," "or") or a semicolon.
- Incorrect: I love pizza, it’s my favorite food.
- Correct: I love pizza; it’s my favorite food.
Or: I love pizza, and it’s my favorite food.
A comma splice creates a run-on sentence, and that can confuse readers by blurring the boundaries between distinct ideas. To fix a comma splice, you can either:
- Add a coordinating conjunction (for, and, nor, but, or, yet, so) after the comma.
- Replace the comma with a semicolon (if the clauses are closely related).
- Split the sentence into two complete sentences with a period.
2. Misplacing Commas in Compound Sentences
A related but slightly different error happens when commas are placed incorrectly in compound sentences. In English, a compound sentence consists of two independent clauses joined by a conjunction. The comma placement before the conjunction can be tricky.
- Incorrect: I went to the store but, I forgot my wallet.
- Correct: I went to the store, but I forgot my wallet.
The general rule here is that when joining two independent clauses with a coordinating conjunction (for, and, nor, but, or, yet, so), you should place a comma before the conjunction.
However, if the clauses are short and closely related, you might skip the comma, though this is more of a stylistic choice than a rule:
- I went and I saw (no comma needed).
3. The Serial Comma (Oxford Comma)
The serial comma—or the Oxford comma—is used before the final "and" or "or" in a list of three or more items. While its use is standard in American English (especially in academic writing), British English tends to omit it in some contexts.
- Incorrect (without serial comma): I bought apples, bananas and oranges.
- Correct (with serial comma): I bought apples, bananas, and oranges.
In more complex sentences, omitting the serial comma can lead to ambiguity:
- Ambiguous: I invited my parents, JFK and Stalin.
- Clear: I invited my parents, JFK, and Stalin.
So, if you want to avoid confusion, it’s often safer to use the serial comma, especially when the items in your list might be misinterpreted without it.
4. Comma After the First Item in a List
While the serial comma is sometimes debated, one thing is absolutely clear: you should not place a comma after the first item in a simple list.
- Incorrect: I bought, apples, bananas, and oranges.
- Correct: I bought apples, bananas, and oranges.
This error is a sign of over-punctuation. The purpose of commas in a list is to separate items, so adding an extra comma after the first item creates an unnecessary break in the sentence and disrupts the flow.
5. Commas with Introductory Phrases or Clauses
Introductory elements—whether phrases or clauses—often require a comma to separate them from the main part of the sentence. Failing to use a comma here can make your sentence harder to follow.
- Incorrect: After the meeting we went to lunch.
- Correct: After the meeting, we went to lunch.
This rule applies to introductory adverbs, phrases, and dependent clauses. The comma marks a pause and signals that the introductory part of the sentence has ended and the main clause is starting.
Examples:
- Suddenly, the lights went out.
- In the morning, I like to drink coffee.
6. Overusing Commas (Comma Overload)
Sometimes, people get a little too excited about using commas and place them unnecessarily throughout their sentences. Overusing commas can create a choppy, disjointed reading experience and make your writing harder to follow.
- Incorrect: She, went, to the store, to buy, some milk.
- Correct: She went to the store to buy some milk.
To avoid comma overload, make sure you’re using commas for a reason—either to separate items, clauses, or phrases, or to indicate a pause for clarity. Don’t use commas just because you feel there should be a pause; it’s better to let the natural rhythm of the sentence guide you.
7. Using Commas with Restrictive vs. Non-Restrictive Clauses
Commas should not be used with restrictive clauses, but they should be used with non-restrictive clauses. A restrictive clause provides essential information about the noun it modifies, while a non-restrictive clause adds extra, non-essential details.
Incorrect (restrictive clause): The book, that she gave me, is great.
Correct (restrictive clause): The book that she gave me is great.
Incorrect (non-restrictive clause): The book that she gave me, is great.
Correct (non-restrictive clause): The book, which she gave me, is great.
Non-restrictive clauses (often starting with which, who, whom) are separated by commas, while restrictive clauses (often starting with that) are not.
8. Commas with Direct Addresses
When you’re directly addressing someone or something, commas should be used to set off the name or title of the person or thing being addressed.
- Incorrect: Let's eat John.
- Correct: Let’s eat, John.
In this case, the comma helps to clarify that you’re addressing John (not stating that you’re going to eat John). This rule applies whether you’re using someone’s name, a title, or a term of endearment.
9. Commas with Coordinating Adjectives
When you have two adjectives that modify the same noun and are equal in importance, you should use a comma between them.
- Incorrect: She wore a red silk dress.
- Correct: She wore a red, silk dress.
However, if the adjectives build on each other (i.e., one adjective modifies the other), no comma is needed.
- Incorrect: She wore a little, black dress.
- Correct: She wore a little black dress.
10. Commas with “Too” and “So”
Words like “too” and “so” can often be followed by commas, but it depends on the context:
Incorrect: It was too, late to go out.
Correct: It was too late to go out.
Correct (with a pause): It was too, too late to go out.
In the first case, “too” simply modifies “late” and doesn’t need a comma. In the second case, “too” is repeated for emphasis, and a comma is appropriate.
Final Thoughts: Commas Aren’t Just Decorations!
Commas are much more than just decorative punctuation marks—they’re essential tools for clarity, flow, and meaning. Misusing them can lead to confusion and unintended meanings, while proper comma use can make your writing easier to understand and more pleasant to read.
By being mindful of the common mistakes listed above—and by understanding the purpose and function of commas—you’ll be well on your way to mastering punctuation in English. So, the next time you write, remember: a well-placed comma can be the difference between a clear idea and a confusing jumble of words.
