A compound sentence is one that is comprised of at least two independent clauses (clauses that can stand on their own, grammatically, as individual sentences).  In other words, a compound sentence is a longer sentence made up of shorter sentences within it. 

We often see a compound sentence punctuated with a comma and a coordinating conjunction (for, and, nor, but, or, yet, so). However, the two independent clauses can be combined with a semicolon or colon, and, in fact, the effect of using the semicolon is to call attention to the connectedness between the ideas expressed in the two independent clauses.  The semicolon and colon can help break up the monotony of academic writing by giving such writing a stylistic flare.

A semicolon can be used to join independent clauses in many compound sentences, but the situation must call for it.  It is normally used if the writer wants to slow the reader down.  In order for a semicolon to be used correctly, the writer must determine that the second independent clause is related to the first one but that it doesn’t define or give further explanation of the first one.

Ex. Joey decided to go back to school; he visited the school’s Web site as soon as he made this decision.

Notice how the second independent clause is related to the first one.  It doesn’t necessarily describe or further clarify why Joey made the decision.  It merely discusses what he did about the decision.

*A semicolon is used correctly in a compound sentence if it can be replaced with a comma and “and” without compromising the meaning or integrity of the sentence.   

Use a colon to join two independent clauses in a compound sentence if the second independent clause further explains, expands, or illustrates the first independent clause.

Ex. Joey decided to go back to school: he understood that earning a degree was the best way to maintain a competitive edge in the workforce.

Ex. My walk in the park wasn’t so pleasant:  I was chased by a dog for about ¼ of a mile.

These examples illustrate how the colon is used to indicate forthcoming information.  The colon seems to say, “Here comes a detailed explanation.”  The second clause in the sentence sometimes answers the question “Why?”

Along with our website, we recommend the following site:  The Creative Teaching Site’s Humorous Grammar Rules.  This site contains a list of tongue-in-cheek grammar guidelines that inform while providing a good chuckle.

Test your understanding by choosing the correct punctuation in each of the following sentences.

1. It wasn’t an ordinary day ( : or ; ) I woke up and discovered that I had a winning lottery ticket.

2. Amanda wants to make sure that she doesn’t miss the fauvist art exhibit at the museum ( : or ; ) she heard that an original Matisse painting will be on display.

3. We are going on a family vacation to Cancun this summer ( : or ; ) the first thing I want to do upon arrival is swim with the dolphins.

4. Josie desperately needs to go grocery shopping ( : or ; ) her cupboards have been empty for several days.

5. The movie must have lasted longer than I thought it did ( : or ; ) my legs were stiff as I walked out of the theater.

Answers

1. It wasn’t an ordinary day: I woke up and discovered that I had a winning lottery ticket.

2. Amanda wants to make sure that she doesn’t miss the fauvist art exhibit at the museum: she heard that an original Matisse painting will be on display.

3. We are going on a family vacation to Cancun this summer; the first thing I want to do upon arrival is swim with the dolphins.

4. Josie desperately needs to go grocery shopping: her cupboards have been empty for several days.

5. The movie must have lasted longer than I thought it did: my legs were stiff as I walked out of the theater.

Grammatically Correct is a grammar tip of the week created by Academic Center Peer Writing Tutors at the University of Houston-Victoria in Victoria, Texas.

Comments about this newsletter should be directed to Summer Leibensperger, leibenspergers@uhv.edu.

Subscribe/Unsubscribe/View Archive