The Grammarphobia Blog

Colon treatment

Q: My boss wants to use the following sentence in an article for a trade journal: “A successful company must focus on its ability to: plan, improvise, and create.” The use of the colon here is awkward, and I suspect incorrect. This would be an easy edit, but what is the specific grammatical crime I can cite?

A: You’re right. That colon is inappropriate here.

Many people routinely stick a colon in front of every series or list. But that’s not always kosher, especially if the list is introduced by a verb or a preposition.

The trouble is that it’s generally incorrect to use a colon to separate a preposition or a verb from its object. So a series that’s introduced by a preposition or a verb shouldn’t ­­have a colon in between.

Garner’s Modern American Usage (3rd ed.) has several warnings about misused colons, including “Don’t put one between a verb and its complement or object” and  “Don’t put a colon between a preposition and its object.”

In the sentence you cite, the boss uses a colon to divide “to” from the series that follows. In the phrase “to plan, improvise, and create,” the word “to” is a preposition with three objects: the infinitives “plan,” “improvise,” and “create.”

No, the word “to” in a phrase like “to plan” isn’t part of the infinitive. It’s a prepositional marker that tells you an infinitive is coming. We’ve written about this before in explaining the “split infinitive” myth.

Some language types disagree with the terminology above, but the Oxford English Dictionary defines “to” as a preposition when it’s used in front of an infinitive. And standard dictionaries do, too.

Getting back to your question, the boss’s sentence would also have been incorrect if written like these:

­(1) “A successful company must focus on: planning, improvising, and creating.” (This is another example of a preposition separated from its objects.)

(2) “A successful company must: plan, improvise, and create.” (This illustrates a verb separated from its complements.)

Neither of those sentences needs a colon.

The new 16th edition of The Chicago Manual of Style also warns about such misuses of colons:

“Many writers assume—wrongly—that a colon is always needed before a series or a list. In fact, if a colon intervenes in what would otherwise constitute a grammatical sentence—even if the introduction appears on a separate line, as in a list—it is probably being used inappropriately.

“A colon, for example, should not be used before a series that serves as the object of a verb. When in doubt, apply this test: to merit a colon, the words that introduce a series or list must themselves constitute a grammatically complete sentence.”

The Chicago Manual uses these examples.

Correct: “The menagerie included cats, pigeons, newts, and deer ticks.”

Incorrect: “The menagerie included: cats, pigeons, newts, and deer ticks.”

The Cambridge Grammar of the English Language (page 1744) also notes that a colon is generally not used to separate a verb from its complement or object.

Finally, Pat’s grammar and usage book Woe Is I offers this advice on the use (or rather the nonuse) of the colon:

“Don’t use a colon to separate a verb from the rest of the sentence, as this example does. In Harry’s shopping bag were: a Bordeaux, a Beaujolais, and a Burgundy. If you don’t need a colon, why use one? In Harry’s shopping bag were a Bordeaux, a Beaujolais, and a Burgundy.”

Some of these examples don’t apply to the specific sentence you’ve asked about, but they’re worth noting. Every bit of support helps when you have to correct your boss.

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