TIP 10 Watch out for ambiguity.

Write unambiguous sentences. Train yourself to spot words and concepts that a reader could misconstrue. Some ambiguities are fairly easy to notice, as in the following sentence: “John told Dan that he was about to be fired.” Which of them is about to lose his job? The answer is ambiguous.

The word “occasionally” is ambiguous. Will shares occasionally rise in value when risks are disclosed? Or will shares typically rise as long as risks are disclosed only occasionally? We can’t tell for sure. And while readers can sometimes figure out your meaning from the sentence’s context, they are using RAM to do so — RAM that they could otherwise spend in productive ways, such as focusing on your main point.

There are many ways to remove ambiguity from your writing. You can use a synonym, move words within a sentence, revise the sentence, or use punctuation to save the reader from becoming confused. For instance, the above example could be revised to read in either of these two ways: “Disclosing risks to investors will occasionally increase share value” or “Shares usually rise when a company provides occasional disclosures to investors about the risks that the company faces.” Even if you need to add a few words to prevent ambiguity, do so. Brevity is a great goal, but it should not be achieved at the expense of clarity.

Two words deserve special mention in any discussion about ambiguity: “this” and “such.” A writer may intend for either of those words to refer to (i) one noun that she just mentioned or (ii) all of the nouns that she just mentioned. Further, “such” can refer to other, unspecified nouns that have some similarities to the noun(s) that the writer just mentioned. Consider this sentence: “Four lawyers angrily called me to discuss whether to settle their clients’ cases. This meant that such cases would soon be resolved.”

What does “this” mean? Will the case settle because the lawyers were angry? Because there were four of them? Because they opened the door to settlement talks? Or all of the above? And does “such” refer to the cases of the four angry lawyers? To all similar cases in which you’re involved? To all cases, everywhere, that resemble the cases that the four lawyers are handling?

Using “this” as an adjective is fine. Thus, in the above example, no ambiguity is created by writing “This tone suggests that they plan to settle.” But when “this” becomes a pronoun or when we use “such” as an adjective — or God forbid, “such” as a pronoun, like “and such” — those words almost always produce vague, ambiguous sentences.