Colons

Writers often use the colon to introduce a list. Be sure that the colon follows a complete independent clause. Do not use a colon immediately after a verb or a preposition. This interrupts an independent clause and is incorrect. The following examples use colons incorrectly:

For a good day at the beach, you must bring: sunscreen, cold drinks, and a radio.
Her favorite writers are: Robert Heinlein, Isaac Asimov, and Harlan Ellison.
Her favorite meal consisted of: Coke, french fries, and a sandwich.

The first and second examples are incorrect because the colon interrupts the independent clause by separating the verb from its object. The third example is incorrect because the colon separates the preposition from the object of the preposition.

Consider the following correct revisions for each of the above examples:

For a good day at the beach, you must bring sunscreen, cold drinks, and a radio.
For a good day at the beach, several items are necessary: sunscreen, cold drinks, and a radio.

Her favorite writers are Robert Heinlein, Isaac Asimov, and Harlan Ellison.
She has several favorite writers: Robert Heinlein, Isaac Asimov, and Harlan Ellison.

Her favorite meal consisted of Coke, french fries, and a sandwich.
Her favorite meal consisted of the following items: Coke, french fries, and a sandwich.

Use colons in the following conventional situations:

Titles and subtitles
Darkest Night: Conscience in America

Time and biblical quotations
12:45 AM
John 3:13

Salutations in business letters
Dear Ms. Elliot:

Place of publication and publisher
New York: Longman Books, 2004

Which sentence is correct? Her backpack contained: a first aid kit, packages of dried fruits and nuts, and a change of clothes. Before you leave, make sure you touch base with these people: your parents, your music instructor, and your boss at the bookstore.