ColonsA colon (:) is a punctuation mark used as a separator. It is also called a full colon.
Colons are seen:
- At the end of an introduction (e.g., I saw the following: ants, a mouse and a rat.)
- Before an end-of-sentence appositive (e.g., He needs just one trait: discipline.)
- Before quotations (e.g., Here's my advice: "Don't jump.")
- In references, ratios, times and titles (e.g., Read Matthew 2:1 before 11:00.)
Examples of Colons in IntroductionsA colon can be used after an introduction.
- Lee likes the following pies: cheese, chicken and mushroom, and beef and ale.
- The Victorian printing set is missing the following characters: Q, R, K and the question mark.
Examples of Colons with Appositives at the End of a SentenceA colon can be used to introduce an appositive. (An appositive is an "equal term" that renames something previously mentioned.)
- He blamed his divorce on one thing: beer. (Here, the appositive is beer. It renames one thing.)
- There are two reasons why I don't believe the alibi: there's no visa and he's scared of flying. (Here, the appositive is there's no visa and he's scared of flying. It renames two reasons.)
- I would like to change just one aspect of your draft: the words. (one aspect = the words)
- I have one piece of advice for those of you who want to receive the Lifetime Achievement Award: Start early! (Actress Shirley Temple) (one piece of advice = Start early)
(When the appositive is a sentence, it can be written with a capital letter.)
- I have made an important discovery: alcohol, taken in sufficient quantities, produces all the effects of intoxication. (Playwright Oscar Wilde)
Examples of Colons in References, Ratios, Times and TitlesA colon can be used as a separator in references, ratios, times and titles.
- Genesis 1:1 starts "In the beginning God created the heavens and the earth." (Here, a colon has been used as a separator in a Bible reference.)
- It's myth that the ratio of women to men in Nottingham is 6:1.
- According to a study by the University of California, the happiest hour of the day is between 19:00 and 20:00. (Times of the day are more commonly written without colons, e.g., 1900 and 2000.)
- The marathon world record is 2:02:57 (set by Kenya's Dennis Kimetto in Berlin in 2014). The 100m world record is 9.58 (set by Jamaica's Usain Bolt in Berlin in 2009). The 800m world record is 1:40.91 (set by Kenya's David Rudisha in London in 2012). (Colons are used in timings greater than a minute.)
- Many scenes for "Pirates of the Caribbean: Dead Man's Chest" were actually filmed at sea because it is so difficult to replicate water digitally. (A colon is often used to separate a title from a subtitle. A semicolon (;), a comma and the word or are also commonly used for this purpose.)
Examples of Colons with QuotationsA colon can be used to introduce a quotation:
- The guides on Gibraltar Rock always give the same advice: "Leave the apes alone, and they will leave you alone."
You could also opt for a colon if the quotation itself is an independent clause, especially if you intend to start it with a capital letter.
- The prisoner uttered: "Leave me alone." (You could use a comma here.)
Why Should I Care about Colons?There are three good reasons to know about colons.
(Reason 1) Use an end-of-sentence appositive to mix up your writing style, for emphasis and to show off a little.Using a colon to introduce an appositive at the end of a sentence is not common in everyday writing, but it is a good tool to keep in your back pocket for mixing up your sentence structures to keep your writing interesting. Also, an appositive at the end of a sentence has the feel of a punchline and is an effective way to create emphasis. And, yeah, an end-of-sentence appositive will do one other great thing for you too: showcase your writing skills.
- His success is attributed to one thing: determination. (Using this sentence structure emphasises determination.)
(Reason 2) Don't use a colon like a semicolon.A semicolon (;) can be used to merge two closely related sentences into one when the writer feels that a full stop is too much of a speed bump between his sentences. You can't use a colon for this. (Remember, a colon is like an equals sign when it extends a sentence. In other words, the text on the right must be an appositive (i.e., a renaming) of something on the left.)
- Many receive advice: only the wise profit from it. [wrong] (The text on the right is not an appositive of anything on the left. This is two closely related sentences. A semicolon would have worked here, but a colon doesn't. This is a badly transcribed quotation by Author Harper Lee.)
- If stock market experts were so expert, they would be buying stock: they would not be selling advice. [wrong] (The text on the right is not an appositive of anything on the left. A colon doesn't work here.)
(Reason 3) Avoid a colon to introduce a list if your introduction is not an independent clause.If you're using a colon before a normal list (i.e., not a vertical list like bullet points), to keep things grammatically pure, try to write an independent clause for your introduction (shown in bold).
- The team will be the following: Fred Bloggs, Joe Bloggs and John Doe. (The introduction for this list is an independent clause so the colon is justified.)
- The team will be: Fred Bloggs, Joe Bloggs and John Doe. [wrong] (This is a little untidy because the introduction is not an independent clause. The use of the colon would likely raise a tut from strict grammarians.)
- The team will be: (1) Fred Bloggs.
(2) Joe Bloggs.
(3) John Doe.
(Be aware that some of your readers might view even this as sloppy.)
- The following points were noted during fire-safety survey: (1) Fire exits blocked by empty PC boxes.
(2) Batteries dead in smoke detectors.
(3) Waste-paper bins used as ashtrays.
(The introduction is an independent clause. Well done. Tuts avoided.)
- The winners are: John, Sarah and Simon. [wrong] (This is untidy. "The winners are John, Sarah and Simon" would be safe.)
- The winners are the following: John, Sarah, and Simon. (An introduction with the following might feel incomplete because it's obvious there is still more to come, but, from a grammatical perspective, it's good enough to create an independent clause.)
- Contact us by: (1) Phone: 01908 311267
(2) Email: firstname.lastname@example.org
(3) Twitter: @liontamers
- There are three good reason to use a colon with an appositive at the end of sentence: to spice up your writing, to emphasise a point and to show off.
- You can't use a colon to merge two closely related sentences into one. That's what a semicolon is for.
- When introducing a list with colon, consider using the words the following to create an independent clause to justify your colon.
- When introducing a list that isn't a vertical list (e.g., bullet points), avoid a colon if your introduction is not an independent clause.
- When introducing a quotation, consider a colon if your introduction or the quotation itself is an independent clause.