Colons
A colon introduces information that illustrates or emphasizes the information that came before the colon. The general purpose of a colon is to direct you to the information that follows it.
One way we might use a colon is to introduce a list in a sentence.
Example: Susie wants three types of fruit: bananas, apples, and oranges.
The colon here tells us that the writer is about to list the three types of fruit that Susie wants.
Another way we can use colons is to separate two independent clauses when the second clause is directly related to the first, and the emphasis is on the second clause. In this case, a colon is not a full stop like a period, but it creates more of a stop than a semicolon would. You might choose to use a colon if you feel it improves the style and emphasis of your sentence.
Example: The director and actors agree with each other: the show is sure to be a success.
Here a colon is used to emphasize that the show is sure to be a success, which is directly related to the first clause expressing that the director and actors agree with each other.
Finally, we can use colons to introduce a quotation.
Example: The love letter included song lyrics by The Cars: “I guess you’re just what I needed.”
Although in academic writing quotations should be integrated as seamlessly as possible, a colon can be used in some situations. This is up to the writer’s stylistic judgement, as well as any instructions given by course instructors.
Be careful not to use a colon to separate parts of a sentence that must be kept together. The most common issues occur when a colon separates a sentence’s subject from its verb or predicate, or a preposition from its objects. This problem often occurs when using a colon to introduce a list.
Example: I want to go to: the grocery store, the pet store, and the theatre.
This colon separates the preposition to from its objects, the grocery store, the pet store, and the theatre. The colon should therefore be removed.
If you have trouble deciding whether to use a colon to introduce a list, try temporarily putting a period in place of the colon. Usually, the information before the colon and list should be a complete sentence. If it isn’t a complete sentence, don’t use a colon to introduce the list.
Example: I want to go to the grocery store, the pet store, and the theatre.
There are some exceptions to this, but it’s a helpful tip to use while still learning about colon use.
Practice:
Answers:
Her favourite colours are blue, green, and purple.
We went to four cities: London, Brantford, Hamilton, and Toronto.
The cashier scanned the items: chips, blueberries, and pasta.
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