The Quick AnswerThe colon has four uses:
(1) To extend a sentence in order to identify something previously mentioned in the sentence.
- I demand one personal trait: discipline. (The colon extends the sentence and identifies "personal trait.")
- I have seen the following: ants, a cockroach, and a rat.
- Read Genesis 1:1 before 07:30.
- He said: "Curiosity killed the cat, but for a while I was a suspect."
More about Using ColonsColons (:) are quite versatile. It is worth learning how to use them — especially how colons allow you to expand on an idea previously mentioned in the sentence. (If you can master this idea, you'll have a useful tool in your writing toolkit.)
(1) Using Colons to Extend a Sentence
Usually, the information on the right is an expansion of whatever is mentioned on the left. For example:
- He blamed his divorce on one thing: beer. (one thing = beer)
- There are two reasons why I don't believe the alibi: there is no visa in his passport, and he is petrified of flying. (two reasons = the visa idea and the flying idea)
- I have made an important discovery: alcohol, taken in sufficient quantities, produces all the effects of intoxication. (Playwright Oscar Wilde) (discovery = the alcohol idea)
(2) Using Colons after Introductions
- The Victorian printing set is missing the following characters: Q, R, K, and the question mark.
He voted for the following films:
(2) The Princess Bride
(3) Shawshank Redemption
Read more about colons for introductions
Read more about using bullet points
(3) Using Colons in References and Times
- I am currently reading "How To Get Your Own Way: Who's Manipulating You?". (Here, the colon is used to separate the main title from the subtitle.)
- Genesis 1:1 starts "In the beginning God created the heavens and the earth." (Colon used as a separator in a Bible reference)
- 07:30 - Breakfast
08:30 - Meet at the lake and prepare the kayaks
09:00 - Select teams
(Colons used as a separator in times.)
(4) Using Colons with Quotation Marks
- It's hard to disagree with Frank Zappa, who said: "Art is making something out of nothing and selling it."
Read more about colons before quotations