Comma Rules

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Comma Rules
7 min

When Should a Comma Be Used?

When should a comma be used? Learn about the rules of comma usage, along with examples of how to use commas in English sentences.

Hannah Yang
By
Hannah Yang
Comma Rules
4 min

Do You Need a Comma Before or After a Prepositional Phrase?

A comma is optional after a prepositional phrase that has fewer than five words, but you should always use a comma after a long prepositional phrase.

Hannah Yang
By
Hannah Yang
Comma Rules

Should You Use a Comma Before or After Quotation Marks? (Examples Included)

In American English, you should always place a comma or period inside the quotation marks. Learn more about whether to place the comma before or after quotation marks.

Hannah Yang
By
Hannah Yang
Comma Rules

Unnecessary Commas: Don’t Make These Common Comma Mistakes!

Unnecessary commas clutter up your writing and make your reader insert unnatural pauses. This affects the overall readability and clarity of your writing.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Should You Use a Comma Before Then or After Then?

Use a comma before then when it connects two independent clauses or when it acts like an interjection. Put a comma after then when it acts as an interjection.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Commas in Dates: Where Do Commas Go Between Month and Year/Day and Month?

Where do you put commas in dates? In the American month–date–year format, a comma goes after the date. But in inverted style dates, you don't need a comma.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Comma Splice: What It Is and How to Fix It (with Examples)

A comma splice occurs when you combine two independent clauses with only a comma. Learn more about how to fix a comma splice in this article.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Do You Need a Comma Before "Such As"?

Use a comma before "such as" if it's part of a nonrestrictive clause. Learn more in this article.

Kyle A. Massa
By
Kyle A. Massa
Comma Rules

Do You Need a Comma After "Thank You"?

You need a comma after "thank you" if you're thanking someone directly or if it's the last part of a letter or email before your sign-off. We break down the rules and give examples in this post.

The ProWritingAid Team
By
The ProWritingAid Team
Comma Rules

Comma Before or After Parenthesis: Correct Usage Explained

Should you use a comma before or after parenthesis? Generally, you should only use a comma outside a closing parenthesis, though there are some exceptions to this rule.

Ashleigh Ferguson
By
Ashleigh Ferguson
Comma Rules

Comma Before That

Do you know when you should use a comma before that? In this article, we’ll show you how to correctly use a comma before that, and give you examples of its proper usage.

Ashleigh Ferguson
By
Ashleigh Ferguson
Comma Rules

Comma Before And

When do you put a comma before and in a sentence? Use a comma before and when joining two independent clauses or in a list of three or more items.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Comma Before Which

Do you put a comma before which in a sentence? If it is part of a non-restrictive clause, you should use a comma before which.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Comma Before Because: Using Because in a Sentence

This article will show you when to use a comma before because in your writing. You normally don’t need a comma, but there are a few exceptions.

Hannah Yang
By
Hannah Yang
Comma Rules

When to Use a A Comma Before "Or"

Use a comma before or when it connects two independent clauses. You can also use a comma before or if it appears in a list. This is called an Oxford comma.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Comma Before "Except": When You Do and Don't Need One

Use a comma before except when it acts as a coordinating conjunction or subordinating conjunction, or when it begins a parenthetical phrase. Learn more here.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Do You Need a Comma Before "So"?

Use a comma before so when it’s acting as a coordinating conjunction to connect independent clauses. Use a comma before and after so when it’s acting as a filler word.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Comma Before "As Well As": How to Punctuate Correctly

Use a comma before as well as when the following information is extra information. Do not use a comma when both clauses are equally important.

Hannah Yang
By
Hannah Yang
Comma Rules

Comma Before Including: When and How to Use Correctly

You should only use a comma before including when the word is introducing a nonessential clause. Learn more about this grammatical rule.

Hannah Yang
By
Hannah Yang
Comma Rules

Comma Before or After But: When and How to Use Commas Correctly

Use a comma before but when it connects two independent clauses. Use a comma after but when it functions as an interjection.

Hannah Yang
By
Hannah Yang
Comma Rules

Comma Punctuation: Rules and Examples for Correct Usage

Comma punctuation is one of the hardest types of punctuation to master. Here are ten rules on when to use commas in sentences, lists, dates, and more.

Krystal N. Craiker
By
Krystal N. Craiker
Comma Rules

Comma Before Which, Where, and Who: When to Use It (with Examples)

Use a comma before which, where, and who when the following information is non-essential. Do not use a comma before a relative pronoun when the information is essential.

Hannah Yang
By
Hannah Yang
Comma Rules

Do You Need to Use a Comma Before or After "However" in Your Writing?

Do you need to add a comma before or after the word "however"? It depends on the situation. Learn the rules for punctuating a sentence with "however" in this post.

Allison Bressmer
By
Allison Bressmer
Comma Rules

3 Awful Oxford Comma Bloopers

Using the Oxford comma is very important. Seriously. Find out why!

GH
By
Gregory Heilers