Writing Center
Youngstown State University

Commas

Commas are an extremely important type of punctuation mark with set rules to guide their use. They are necessary to certain sentence structures to clarify meaning for the reader. Below are the six basic comma rules. They will not cover every situation but will help you in most instances.

1. Use a comma with a coordinating conjunction to connect two independent clauses.

Example: I go to school full time, but I also work.

Tip: The comma is placed after the first clause and before the coordinating conjunction (for/and/nor/but/or/yet/so). However, a comma is needed only if there is an independent clause (sentence) on either side of the coordinating conjunction.

Example: Sally cut the turkey and set the table.

2. Use commas after introductory words, phrases, or clauses.

Examples:

A. Suddenly, the phone rang and startled the dog.

B. Wanting a new CD player, Fred saved his allowance all summer.

C. Since winter is coming, Mary is going to buy a new scarf.

Tip: Words such as if, when, since, although, because, after, and before are subordinating conjunctions and signal introductory elements.

3. Use commas between items in a series of three or more.

Example: They are going to the museum, the park, and the zoo tomorrow.

Note: The comma before the conjunction in a series of three or more is optional.

Tip: If you have commas within the items in a series, use semi-colons to separate the items.

Example: I will travel through Youngstown, Ohio; Boardman, Ohio; Chicago, Illinois; and New Orleans, Louisiana.

4. Use commas to separate lists of adjectives that individually modify a noun.

Example: The small, fuzzy kitten played with a ball of yarn.

Tip: If you can replace the comma with "and" without destroying the meaning, the comma is correct. (The small and fuzzy kitten...)

5. Set off in commas any words, phrases, or clauses--other than restrictive modifiers--that interrupt the structure of the sentence.

Examples:

A. Roses, I think, are better than carnations.

B. Dave, who lives down the street, drives a red Porche.

C. The man who lives down the street drives a red Porche.

6. Use commas between dates, addresses, and geographical names.

Example: He will leave Youngstown, Ohio, on June 15, 1996, for an exciting week in the Caribbean.

E-mail your comments and suggestions to the YSU Grant Team (cardcat@bgnet.bgsu.edu).