The Colon
A colon is formed with two vertical periods and has two primary functions: to introduce something or to separate elements.
Introducing an explanation, example, or appositive
Use a colon before the element you are about to introduce in your sentence.
- Example: When quoting from a text, you must cite the information: list the author or publication where the quotation comes from followed by its page number. (The second statement gives an explanation of the first).
- Example: Kim is never on time for any of her appointments: just last week she arrived thirty minutes late to the Volunteer Council meeting. (The second statement is an example of the first).
- Example: Students at Agnes Scott abide by the Honor Code: a pledge that we will refrain from behaviors such as cheating, stealing, or plagiarizing. (The second statement provides an appositive for the Honor Code.)
Introducing a series, list or quotation
Again, use a colon before the element you are about to introduce in your sentence.
- Example: Since Mom is working late, she gave me a list of things to pick up at the grocery store: eggs, milk,tomatoes, and ice cream. (The second statement is a list.)
- Example: I remember my mother always said the same thing to me each morning as I left for school: "Be sweet and remember that Mother loves you very much." (The colon is placed before the quotation to separate it from the introductory portion of the sentence.)
Separating elements
Colons have several standard uses for separating elements:
- Time (hours, minutes, seconds): 9:45 P.M. 5:13:07
- Biblical chapters and verses: John 3:16 II, Timothy 2:1a
- Titles and subtitles: America’s Sport: A History of Baseball
Common colon mistakes
- Unless it is separating elements, a colon should come only at the end of an independent clause (a phrase that could stand alone as a complete sentence).
- Colons do not follow expressions like "such as", "especially", or "including". Colons should not be placed between a verb and its object or complement, unless the object is a quotation
Correct—My favorite colors are red, blue, and white.
Incorrect—We frequent several Decatur restaurants such as: Butter and Cream and Raging Burrito
Correct—We frequent several Decatur restaurants, such as Butter and Cream and Raging Burrito
Incorrect—When John saw his new car, he said: "I can't believe it's actually mine!"
Correct—When John saw his car, he said, "I can't believe it's actually mine!"