Commas are Enigmatic

By Amy Salisbury

Commas are enigmatic—you need them more than you might think, but overuse leads to confusion.

Say you have a sentence with a common conjunction (for, and nor, but, or, yet, so). You probably think you need a comma before that conjunction in any case. But that’s not the case!

This sentence is fantastic and rather short.

In the above sentence, I didn’t use a comma for one specific reason: “rather short” is not a complete sentence.

Commas are necessary whenever the clause following the conjunction is a complete sentence.

This sentence is fantastic, and I made it slightly longer than the example I used earlier.

“I made it slightly longer than the example I used earlier” is most certainly a complete sentence. You’ve got a subject and a verb to attest to.

What about commas that go in the middle of sentences? What about those sentences, like this one, that have little asides within them?

That last sentence contained a nonrestrictive clause, meaning “like this one” was a part of the sentence that could be removed completely without sacrificing the meaning of the sentence.

Sometimes commas even dictate the meaning of a sentence:

Time to eat grandma.

Time to eat, grandma.

The comma before “grandma” completely changed the meaning of that sentence. Naturally, the writer of that sentence is most likely not a cannibalistic maniac, but without a piece of punctuation, the reader would never know the difference.

However, sometimes commas come at the beginning of sentences with what’s called “introductory phrases.” “However” introduces my point about these types of phrases. Other introductory phrases include “sometimes,” “nonetheless,” “on the other hand,” and many others.

If you have trouble with comma placement, leave your revision for later instead of editing as you go. And, of course, make an appointment at the Writing Center for all your comma use needs.