Ever been chided for doing something you know isn’t wrong? Your brother-in-law insists that guacamole is made only with lemon—never lime—and that you’ve ruined it with your tiny green citrus. His mama taught him to make it with lemon, and he doesn’t care how much you cite Alton Brown.

The same goes when you’re writing at work. Although modern grammarians and reference books firmly assert that all five of the “rules” I’m going to give you are baseless, they’ve been taught as law in many schools—especially to people old enough to be your boss.

So read up. Be informed. Know they are myths—and follow them in your writing at work anyway. Believe me, it makes life easier.

1. “Data” Can Only Be Plural

In Latin, “data” is the plural of “datum.” Therefore, some people insist that “data” can only be plural in English ("the data are here," not "the data is here"). Now, these same people would never ask you to send them the meeting “agendum,” even though the “agenda/agendum” pair is just like “data/datum.” And that’s because English is a rogue and has no problem giving a makeover to words it takes from other languages.

Nevertheless, you’re safest keeping “data” plural. If it sounds weird to you, use a different word, such as “information” or “results.”

Don’t: This quarter’s data is going to get us fired.

Do: This quarter’s results are going to get us fired.

2. Never Split an Infinitive

You split an infinitive when you put an adverb between “to” and a verb—for example, “to boldly go.”

The rule against splitting infinitives was made up by a few fellows in the mid-1800s, and even they weren’t that adamant about it. They generally thought it was better to avoid splitting infinitives, but they didn’t say that splitting was the unforgivable sin that some people seem to think it is today.

Even though splitting isn’t wrong, moving the adverb rarely changes the meaning of your sentence. Just do it.

Don’t: She wanted to loudly tell her boss to pound sand.

Do: She wanted to tell her boss loudly to pound sand.

3. Don’t End a Sentence With a Preposition

This “rule” was made up in 1672 by John Dryden—a writer so famous in his time that some refer to the years of his prime as the Age of Dryden. His influence assured that the rule made it into schoolbooks, and it’s been widely taught ever since. Nevertheless, there’s no logical basis for the rule, and modern language experts have fought back in force.

The only reason you’ll find in most current language books for avoiding an ending preposition is to save you from offending someone who still thinks it’s wrong. But, in the workplace, that’s actually not a bad reason.

Don’t: Now that’s something I hadn’t thought of.

Do: Now that’s something I hadn’t considered.

4. “Slow” is Never an Adverb

Fussbudgets will tell you that signs shouldn’t say “drive slow”—they should say “drive slowly.” The bearers of this news ignore the existence of flat adverbs (those that don’t end in -ly). Even William Strunk Jr., of Elements of Style fame, used them: Co-author E.B. White reported that Strunk often told students, “If you don’t know how to pronounce a word, say it loud.”

Still, the belief that flat adverbs are wrong is so widespread, it’s safer to use the non-flat adverb form.

Don’t: He talks so loud we can hear him three cubes down.

Do: He talks so loudly we can hear him three cubes down.

5. Only Food is Done; Projects are Finished

You’ve probably been chided by someone at the dinner table for saying you’re “done” instead of “finished,” but that aunt or grandfather was holding on to a belief that doesn’t make any sense. This “rule” surfaced in the early 1900s, but the style guide that started it gave no reason. The Merriam-Webster Dictionary of English Usage speculates that the advice was based on bias against the usage’s “Irish, Scots, and U.S.” origin.

You can argue the point with Aunt Millie, but at work, there’s no harm in sticking with “finished.”

Don’t: I’m done with this project.

Do: I’m finished with this project.

In the workplace, it’s not always about what’s right and wrong—it’s about how you play the game. And yes, that includes grammar.

Photo of books courtesy of Shutterstock.