The poor semicolon gets absolutely no respect! Have you noticed that it gets dragged into more sentences than any other mark — except for the dash — usually in the wrong place? Or in place of a comma or colon, either of which would be happy to take its place? Too many writers have no idea what to do with it, and I hope this post will help.
I teach a three-hour course called “Brush Up on Your American Grammar Skills,” and I keep my usage of various punctuation marks down to a bare minimum. The course is intended for business professionals, whose goal is usually to communicate a message clearly. And I believe in the KISS principle — my version of it anyway:
So, here are the three — yes, only three — rules for using this particular mark in business writing. If you are writing a thesis of some kind, you might find another rule or two, but first — let’s all master these three.
1. Compound Sentences: Use a semicolon to join two independent clauses (simple sentences) together. Each sentence could stand on its own (each has a subject and predicate and is a finished thought), but you choose to join them because they work better as a complete thought. Simply replace the period of the first sentence with a semicolon, and you’re good to go!
Mary had a sandwich for lunch; John opted for a burger.
John’s running late; Susan will fill in for him until he arrives.
Each of the examples above could be separated into two sentences, or you could use one of the seven coordinating conjunctions (and, but, for, nor, or, so, yet) in the middle with a comma.
Mary had a sandwich for lunch, but John opted for a burger.
John’s running late, so Susan will fill in for him until he arrives.
2. Transitional Expressions: If you link independent clauses with terms such as for example, however, moreover, namely, nevertheless, or therefore, replace the period of the first sentence with a semicolon. You may always choose, of course, to keep the sentences separate.
We’ll go to the movie. However, we’ll wait until the 9 p.m. show.
We’ll go to the movie; however, we’ll wait until the 9 p.m. show.
She’s fully qualified for the job. For example, she’s had ten years’ experience.
She’s fully qualified for the job; for example, she’s had ten years’ experience.
3. Items in a Complex Series: Items in a complex series contain required internal commas, so we use semicolons to separate the series sections. Think of the semicolon as an “internal traffic cop”; it’s not an end mark of punctuation, but within a sentence of this type it indicates a section is finished.
In the example below, it’s especially difficult to figure out who is who when each occupation doesn’t even have a name with it! But even if it did, it would be a poorly and incorrectly written sentence. (The sentence would be much clearer if written with bullet points, but sometimes we write just a sentence to conserve space.)
Who is who?
Please invite the Chairman, Ann Murphy, the Executive Vice President, Sam Smith, the Director of Investor Relations, and Penny Smith, the Chief Financial Officer.
If you read all the way to the end, the sequence becomes clear: the name comes before the occupation in the sentence. That means that “Chairman” has no name attached to it — in this sentence.
Please invite the Chairman; Ann Murphy, the Executive Vice President; Sam Smith, the Director of Investor Relations; and Penny Smith, the Chief Financial Officer.
Using the semicolon after “Chairman” is intended to show that the name following does not belong to it. Will that work with every reader? Nope. Nothing works with everyone, but here we’re trying to make it easier to understand for most readers. Again, I like bullet points with lists like this.
Maybe even easier?
Please invite the Chairman; the Executive Vice President, Ann Murphy; the Director of Investor Relations, Sam Smith; and the Chief Financial Officer, Penny Smith.
One more example:
The firm has offices in Boston, Mass.; Cranston, R.I.; Atlanta, Ga.; and San Diego, Calif.
The last example shows that again, there are required commas (between the cities and the states) but the state name ends a specific section of the sentence, thus requiring a semicolon.
Here are a few NO-NOs:
Mary said to John; “Are we going to the movies tonight?” (Use a comma.)
John and Mary went to the movies; but they arrived late. (Use a comma.)
Dear John; (Use a comma.)
Dear Mr. Smith; (Use a colon.)
Although they tried to plan; they failed. (Use a comma.)
I need just three things to finish; scissors, glue, and tape. (Use a colon.)