Commas and Essential Information

Comma Chameleon

When the song “Karma Chameleon” by Culture Club came out in 1984, I was relatively young. And I was just certain that the lyrics were not, “karma, karma, karma, karma, karma chameleon,” but, “comma, comma, comma, comma, comma chameleon.”

I guess I’ve always had punctuation on the brain.

In any case, the chameleon is a good representative of the comma, because commas are tricky. There are literally dozens of rules about commas; I could do a ten-part series on comma use and still not cover all the bases.

That said, I do have a comma usage rule to share that you may not know. Most people know to use commas to separate items in lists and to set off words or phrases that otherwise interrupt the flow of a sentence. A comma rule of thumb that many people do not know refers to essential and non-essential phrases and words in a sentence. And it’s whether those words are essential that determines whether or not to use a comma.

For example, I have two daughters. Because both of my children are the same gender, if I write the sentence, “My daughter Emma is really excited about kindergarten,” placing Emma’s name in the sentence is essential to the meaning of the sentence.  Otherwise, you wouldn’t know which daughter I am referring to.

On the other hand, I only have one husband. If I write a similar sentence, “My husband, Bill, played college football,” I need the commas. If I don’t use the commas, it indicates to my readers that naming my husband is essential, thereby giving the idea that I have more than one husband and am breaking the polygamy law. And that’s not the impression I wish to give.

Think of it this way: If I remove Bill from the example sentence, the sentence still makes complete sense and you know exactly to whom I am referring. If I remove Emma, however, it leaves doubt.

It’s not just people’s names that need to be treated this way when it comes to commas. Any number of other things need the same care. Consider the following examples:

            Cold Play’s song “Viva la Vida” is one of my favorites.

            Michael Crichton’s first book, The Andromeda Strain, came out in 1969.

           

Cold Play performs dozens of songs, so the title of the song is necessary to the sentence and does not require commas. And although Michael Crichton published 25 books in his life, he only had one first book, so that title, when mentioned as above, needs the commas because it’s not essential to the meaning of the sentence.

This same rule of essential versus non-essential use is the drive behind another grammatical issue: restrictive and nonrestrictive relative clauses. Those probably sound intimidating, but they’re really not.