Colons

How They Are Used

Colons are used to introduce a clause that is explains, exemplifies, or specifies what was mentioned before the colon. The clause after the colon might be a list, a sentence fragment, or possibly even a complete sentence.

Here is an example of a properly used colon:

There are three reasons I like to read: it's fun, it's educational, and it's a good way to relax.

In this sentence, the colon introduces the list of reasons.

A Complete Sentence Should Always Come Before a Colon

When a colon is used correctly, it should always come at the end of a complete sentence. For example, it would be incorrect to say "The three reasons why I like to read are: it's fun, it's educational, and it's a good way to relax." Since "The three reasons why I like to read are" is not a complete sentence, this is not a correct use of a colon.

There May or May Not Be a Complete Sentence After the Colon

While we always need a complete sentence before the colon, what follows the colon is more flexible. It may be a complete sentence, or it may be a fragment. For example, we often have a list, which is not a complete sentence, coming after the colon: "I went to the store to buy three things: a shirt, a pair of pants, and a pair of shoes." Or we can have other types of dependent clauses after a colon, like in this example: "I went to the store for one reason: to buy a shirt." But, sometimes we will see a complete sentence after the colon, like in this example: "The meeting was a disaster: the speaker was late, the room was too small, and the projector didn't work." Here we have a complete sentence after the colon, and the colon is appropriate because what comes after explains why the meeting was a disaster.

If You See a Colon in an Answer Choice

If you see a colon in an answer choice, the first thing you should check is whether you have a complete sentence ending at the colon. If you don't, you can eliminate it. If you do, then it's probably the correct answer.

While it's most likely the correct answer once you identify that the sentence ending with the colon is complete, this isn't always the case. There are two additional things you should check:

Check that the colon makes sense. Does it introduce a clause that explains, exemplifies, or specifies what was mentioned before the colon?
- It might be a list, a sentence fragment, or a complete sentence.
Make sure the clause after the colon is grammatically sound.
- Just because you don't need a complete sentence after the colon doesn't mean that anything flies grammatically.
- Watch out for comma splices. A comma splice is a sentence that has two independent clauses (complete sentences) joined by a comma without using a coordinating (FANBOYS) conjunction.
  - For example, "He went to the movies, he saw Gladiator 2."
- Also watch out for run-on sentences. A run-on sentence is a sentence that has two or more independent clauses (complete sentences) without proper punctuation connecting them (not even a comma).
  - For example, "The dog barked loudly at the mailman he was very protective of his house."

If you don't see any issues after checking the above, then you can confidently select the answer choice with the colon.

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