Have you ever wondered what’s the difference between a colon and a semicolon? When are they even appropriate to use? Whether you’re taking the ACT or the SAT, these colon rules are helpful for any English class. This blog covers the colon, AKA the symbol with two dots (:), not to be confused with the semicolon (;).
The First Rule of Colons
The colon, 98% of the time, only comes after an independent clause. Do not put a colon after a sentence that isn’t a complete thought! Make sure you check the sentence that comes before the colon, and if it isn’t an independent clause, then the colon is wrong.
WRONG: Walking on the boardwalk: I peered at the seagulls in flight.
WRONG: While I was on the boardwalk: I peered at the seagulls in flgiht.
CORRECT: I walked on the boardwalk: an old pedestrian zone that captured the enchanting local color.
The Second Rule of Colons
Whenever you use a colon, whatever comes after the colon must describe, detail, define, give an example of, or further elaborate on an idea introduced in the information before the colon. If you see a colon and the information after the colon doesn’t further explain an idea introduced earlier in the sentence, the colon is wrong!
Whatever follows a colon can be most any type of grammatical construction—a clause, a phrase, a word, or a list are all appropriate. What matters most is content: does the information after the colon further explain the idea before the colon?
WRONG: I went walking on the boardwalk: later, I peered at the seagulls in flight.
CORRECT: I walked on the boardwalk: an old pedestrian zone that captured the enchanting local color.
Don’t Believe the Lie that Colons Always Come Before a List!
You may have heard this from an English teacher in the past. Colons don’t only come before a list though. Of course, sometimes you will see colons before lists, but in order for them to do so the two rules of colons must still be followed. For example, if you use lead in language like “consists of,” “for example,” or “such as,” then you don’t need a colon. You can either use lead in language, or use a colon instead.
WRONG: My homework consists of: a paper, practice problems, and an oral report.
CORRECT: My homework consists of a paper, practice problems, and an oral report.
CORRECT: My homework has a few parts: a paper, practice problems, and an oral report.
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