Print this page

Commas, Semicolons, and Colons

When and how to use commas:

                    He said, “Let’s go,” and we did.
                    He said we should go, and we did.

                    He had heard about “oleo,” but he didn’t know what it was.

                    On the other hand, many diets decrease stamina and strength.
                    As a matter of fact, American football was derived from rugby.
                    Many people, however, are allergic to cats.

                    I hate to say this, John, but this relationship just isn’t working out.
                    You like chocolate, don’t you?
                    Well, I might have time for lunch with you next week.
                    Yes, you must do the homework.

                    It was raining, and I was hurrying to get home.
                    She felt terrible, but she went to class anyway.

                    On the way home, I stopped to buy groceries.
                    Because it was raining, I took a taxi home.
                    To our surprise, they were brothers.

                    He bought bananas, apples, oranges, and cheese.
                    She had long, dark, straight, thick hair.

                    My parents, who met each other in 1932, have been married for 50 years.
                    Hikers need sturdy shoes, which may be expensive.

When not to use commas:

                    Incorrect: Joe and Jill, went to the store.
                    Correct: Joe and Jill went to the store.

                    Incorrect: I went home, and went to bed.
                    Correct: I went home and went to bed.

                    Incorrect: I bought two, more apples.
                    Correct: I bought two more apples.

 When and how to use semicolons:

                    The book is informative; it has helpful charts and graphs.
                    My brother is going to Spain for the summer; he will be studying Spanish.

                    I like big, purple shirts; red, high-heeled shoes; and fluffy, yellow pillows.
                    I live with Larry, a student; Moe, an executive; and Curly, a cop.

                    He had heard about “oleo”; he didn’t know what it was.

When and how to use colons:

                    I have two favorite colors: red and purple.
                    She traveled to the following countries: England, Italy, and Japan.

                    He explained “oleo”: it’s a non-dairy butter substitute.

Adapted from: The Harbrace College Handbook (12th ed.) by Horner/Webb/Miller and A Writer’s Reference (4th ed.) by Diana Hacker. 

The University Writing Center 2009 | 4400 University Drive MS2G8 | Fairfax, VA 22030 | Tel: 703-993-1200 |