Grammar Tips: When to Use a Colon and Semicolon

The semicolon is one of the most misunderstood forms of punctuation even though the rules for use are fairly simple. Beware, students—ACT creators loves to test on this punctation mark. When do you use a semicolon?

When there are two independent clauses (can stand alone as sentences) on either side. The two clauses are not joined by FANBOYS (coordinating conjunctions: for, and, nor, but, or, yet, so). The semicolon is only correct if it could be replaced by a period. A semicolon is used instead of a period to show that the two independent clauses are related to the same thought.

Examples:

Caitlin left before breakfast; Josh stayed until after lunch.I rented a car and drove to New York; Kris wanted to fly there.While we were at the fair, my dog won a ribbon in the dog show; it hangs proudly in my room.I like cats; however, I am allergic to them. (Note: however is not a coordinating conjunction that takes a comma (FANBOYS only).

Second rule: Semicolons are used in a list of items to help with clarity. The semicolon may be used in a list that has other conjunctions to commas.

Examples:

Several people are coming to my graduation including my aunts, Julie and Cindy; my roommates, Kathryn and Megan; my grandparents; and my parents. (Notice that commas are used to note who the aunts are and who the roommates are. A semicolon is used for clarity. Otherwise the sentence would read: Several people are coming to my graduation including my aunts, Julie and Cindy, my roommates, Kathryn and Megan, my grandparents; and my parents. How many people are coming? Are Julie and Cindy two additional people? Are they aunts? Are they roommates?)

When do we need to use colons? A colon can be used to draw attention to things in your writings: lists, quotes, or thoughts that logically follow an independent clause. (Notice the wonderful example of a colon used here.)

First rule: Use a colon when introducing a list at the end of a sentence.

Example: I need several things to bake my bread: flour, butter, eggs, and yeast.

(Note: do not use a colon between a preposition and a list. Example: Bread is made of flour, butter, eggs, and yeast.)

Second rule: You can use a colon to introduce a quote.

Example: My grandmother said it best: “Never give up on yourself.”

Third rule: You can use a colon to set apart a thought that logically follows what is before it or is a consequence of the clause before it.

Examples: My pets give me the best gift of all: unconditional love. There was one thing that kept me from succeeding in college: my procrastination.

Fourth rule: A colon is used to separate a smaller item from its larger unit (a subtitle from a title; a verse number from a chapter number).

Examples: David McCullough wrote Brave Companions: Portraits in History. That quote can be found in John 1:3.