Rhetoric and Composition/Colons

Colons are used to draw attention to certain words. They are used after an independent clause to direct attention to a list, appositive or quotation, between independent clauses when the second clause summarizes or emphasizes the first clause, or after the greeting in a formal letter. Some examples follow.

Use of Colons

Case	Example	Note
List	I have three sisters: Catherine, Sarah and Mary. Sandwich requires several ingredients: bread, butter, cheese, ham and tomatoes.
Appositive	My mom has three pets: two cats and a dog.
?	There was only one possible explanation: The train had never arrived.
Quotation	In the words of Homer: "Doh!"
Between independent clauses	Life is like a box of chocolates: you never know what you're going to get.
Introduction of a definition	Hypernym of a word: a word having a wider meaning than the given one.	Is a special case of appositive.
After salutation	Dear Sir or Madam:
In a dialogue	Patient: Doctor, I feel like a pair of curtains. Doctor: Pull yourself together!
Separation of title from subtitle	Star Wars Episode IV: A New Hope
Separation of the chapter and the verse numbers of religious scriptures	John 3:14–16 (or John III:14–16) The Qur'an, Sura 5:18
Separation within time of the day	The concert finished at 23:45. This file was last modified today at 11:15:05.

Common Misuse of Colons

Case	Example	Note
Between a verb and its object	Some important computer programs are: Word, Excel and Publisher. Sandwich requires: bread, butter, cheese, ham and tomatoes.	By omitting the colon, the example becomes correct.
Between a preposition and its object	My cars of choice consist of: Honda Accord and Ford GT.	By omitting the colon, the example becomes correct.
After "such as", "including" or "for example"

Bibliography

• W:Colon (punctuation)