When to Use a Comma
The comma is a frequently used type of punctuation that helps separate words and ideas in a sentence. Writers can use a comma in many different ways. Below are some examples of the proper comma rules.
Comma Rules in a Series
Comma Rules: When listing three or more items, insert a comma after all of the items except the last one.
Comma Rules Between Adjectives
Comma Rules: When using two or more adjectives to describe someone or something, insert a comma between the adjectives.
Comma Rules: Generally, do not insert a comma after adjectives that indicate either a number or the size, shape, or age of something or someone.
Comma Rules with Introductory Elements
Comma Rules: Insert a comma after introductory words and mild interjections that come at the beginning of a sentence.
Insert a comma after an introductory prepositional phrase if it contains at least one additional prepositional phrase. You don’t need to use a comma if either the sentence starts with just one prepositional phrase (unless you’d naturally pause after saying it aloud) or the prepositional phrase is very short.
Comma Rules: Insert a comma after a verbal phrase that comes at the beginning of a sentence.
Comma Rules: Insert a comma after an introductory adverb or adverb clause that comes at the beginning of a sentence.
Comma Rules with Interrupters
Comma Rules: Insert a comma to set off words of direct address, such as names, titles, or terms of respect.
Comma Rules with Nonessential Information
Comma Rules: Insert a comma to set off nonessential clauses, participles and participial phrases, and appositives and appositive phrases. Nonessential elements add additional information that isn’t necessary for understanding a sentence’s meaning.
Comma Rules in Compound Sentences
Comma Rules: Insert a comma before the coordinating conjunction that joins two independent clauses in a compound sentence.
Comma Rules with Quotations
Comma Rules: Insert a comma in direct quotations to set off words telling who is speaking. Always place a comma inside of a closing quotation mark.
Comma Rules in Dates
Comma Rules: Insert a comma between a day of the month and a year. If a date is part of a sentence, then insert a comma after the year as well. If only a month and a year are given with no specific day, then do not include a comma.
Comma Rules in Places
Comma Rules: Insert a comma between a city and its state, country, or province. If a place is part of a sentence, then insert a comma after each item in the place’s name.
Comma Rules in Letters
Comma Rules: Insert a comma after the salutation of a friendly letter and also after the closing of either a friendly letter or business letter.
Thank you for your gift!
It was great to see you when we were recently in town.
Comma Rules in Names
Comma Rules: Insert a comma between a person’s name and any abbreviation or acronym that follows it. Many, though not all, businesses follow a similar practice by inserting a comma between their names and any accompanying abbreviations or acronyms.
Comma Rules in Numbers
Comma Rules: In numbers insert a comma after every third digit from the right. (This rule does not apply to zip codes, phone numbers, or house numbers.)