Commas

Using Commas

Rule	Explanation	Examples
Rule 1: Introductory Phrases	Use a comma after an introductory phrase or an adverbial clause that begins a sentence.	For example, this sentence needed a comma. Once upon a time, there lived a wicked witch who loved to eat children for breakfast.
Rule 2: Dependent clause before independent clause	Use a comma after a dependent clause and before an independent clause. Dependent clause markers include words such as: Because, Since, If, When, While, After *See dependent clauses for more information	After I began taking classes, I realized the importance of studying. Because he did not wear his raincoat, Matthew came home drenched to the skin.
Rule 3: Lists and the Oxford Comma	Use a comma to separate words in a series of three or more things. In academic writing, be sure to include a comma before the conjunction (known as the serial comma or the Oxford comma).	I like apples, oranges, and bananas. The Doctor was accompanied by K-9, the Daleks, and his partner.
Rule 4: FANBOYS (Coordinating conjunctions)	Use a comma before a coordinating conjunction *(and, but, yet, or, for, nor, so)* to connect two independent clauses. Never use a comma to connect two independent clauses without a conjunction. Use a semicolon, or start a new sentence.	I thought I was finished with my paper, but I realized I’d forgotten to do my citations. I went to the animal shelter, and I found the perfect dog for my family. WRONG: I looked out the window, it had begun to rain. CORRECT: I looked out the window; it had begun to rain.
Rule 5: Parenthetical phrases (non-essential phrases)	Use a pair of commas to set off parenthetical phrases (non-essential elements) in a complete sentence. In other words, non-essential elements are phrases that can be removed from the sentence and the sentence still makes sense without it.	I made an A, of course, because I revised my paper. Cassandra, his wife of nearly a decade, always managed to be right, although he never listened to her advice.
Rule 6: Contrasting phrases	Use a comma to set off phrases that express contrast.	That backpack is mine, not yours. The Incredible Hulk is strong, but sensitive.
Rule 7: Adjectives for the same noun	Use a comma to separate adjectives that modify the same noun in the same way.	In order to get home, we must travel over several narrow, winding, treacherous roads.
Rule 8: Quotes	Use a comma to introduce quotes. When the quoted material contains more than four lines, it should be formatted as a block quote, and the comma should be omitted.	The Professor said, “I will not tolerate plagiarism in my classroom.” Paul quietly looked at Jefferson and pointed out, “Your head is on fire.”
Rule 9: Locations, Dates, Titles, and Numbers	Use a comma: between a city and a state a date and the year a name and a title when the title comes after the name when writing out long numbers	Hartford, Connecticut, June 15, 1997, Bob Downey, Professor of English 5,456,783 or $14,682
Rule 10: Avoiding Confusion	Use a comma to avoid confusion.	Outside the ground was covered with hungry pigeons. -> This could mean the ground outside an area. Outside, the ground was covered with hungry pigeons. -> This means that you are inside and you are looking outside in to nature.