No, not that colon

When I ask people what type of punctuation causes them the most problems, they usually go straight for commas. However, when I ask how many of them know how to use colons, most just give me a puzzled stare. They don’t know, and they prefer not to think about it. Colons make them uneasy. Colons, however, are actually fairly easy to use once you understand what they do.

The basic rule for colons, stated so that most people understand, is this: what follows the colon must expand on or explain what immediately precedes the colon.

Note that I used a colon in that sentence. What follows the colon is the rule on how to use the colon; what precedes the colon states that this is the rule. Generally, writers use colons just before lists. But the list should expand on what immediately precedes the colon, so what immediately precedes the colon should name the list. Have a look at the next example:

The tester has six main parts:  a dynamometer, a shock-absorbing unit, two grips, a stabilizer bar, a power screw, and a hand wheel.

You notice that right before the colon and the list we have “six main parts”; that names the list. What follows the colon is the actual list.

Where I see colons misused most often is at the end of the introduction of scientific articles where authors list their objectives.

“Our objectives in this research were: 1.) to test X, 2.) to determine Y, and 3.) to analyze Z.”

This is incorrect. A colon does not follow a verb. This can be corrected in one of two ways:

“Our objectives in this research were 1.) to test X, 2.) to determine Y, and 3.) to analyze Z.”

“In our research, we had three objectives: 1.) to test X, 2.) to determine Y, and 3.) to analyze Z.”

You’ll notice that in the first correction, we simply omitted the colon. That is perfectly correct. In the second correction, we rearranged the first part of the sentence to end with the word objectives, which names the list. Either works. I suggest that the second would be better if you want to emphasize the list.

Sometimes, to make the colon work, writers will finish the introductory half of the sentence with “the following”; this works because the list is named. However, at times, using the phrase is less efficient than rearranging the sentence. Usually, the solution is the first of the two above.

Another problem I often see with colons (and even without colons) involves using the word “including”.

There are three types of tourist needs as per experience including: basic, social, and intellectual components.

This sentence doesn’t work for several reasons. You’ll note that it begins with an expletive (there are). In addition, we have a Latin phrase (as per), and then we have a colon, which is used incorrectly. Finally, we have that word, including. Including, by definition, should introduce an incomplete list. If the list is complete, you don’t want to use it. So we can revise the sentence several different ways, depending in part on what the author meant. (It’s not only not correct, it is not concise.) Both possible revisions do not include “including”.

Tourists have three needs: basic needs, social needs, and intellectual needs.

The experiences a tourist has will have three components: basic, social, and intellectual.

 
Something to note here. These sentences do not mean the same thing. An editor will not know what the author has in mind. Making a sentence concise and correct also indicates to an author when an idea is unclear. If the editor got the wrong message, then the author should know where to begin work when revising.