In our previous discussion of comma usage, we showed that non-essential material is set off with commas—enclosed by “basket handles” that allow us to imagine lifting out the non-essential “basket” to see that the remaining sentence retains its basic meaning.
Here, in a nutshell, is the difference between essential and non-essential material:
1. My dog, Watson, is the bane of my existence.
–implies that you only have one dog, and he makes your life miserable. Even if you didn’t tell us his name, when talking about your dog you’d actually be talking about Watson. “Watson” is a non-essential term.
2. My dog Watson is the bane of my existence.
–implies that you have at least two dogs, and only one of them—Watson—is ruining your life. Any other dog you have is blameless. Removing “Watson” from this expression would make it ambiguous—would, in other words, change its meaning. Removing “Watson” would, in fact, risk besmirching the reputation of another dog! The full meaning of the sentence depends on how it’s punctuated.
If you think of those commas in Sentence 1 as basket handles, you’ll see that the “basket” can be removed without injuring the basic meaning of the sentence:
My dog is the bane of my existence.
On the other hand, since “Watson” in Sentence 2 is crucial to the meaning of that sentence, we don’t set it off with commas.
When trying to decide whether a modifying term or phrase is essential, we have to look for the basket. Examples:
3. I spent most of my life waiting for something to happen.
4. I made my living, such as it was, as a writer of fiction.
In each sentence, the underlined material is clearly descriptive. (In Sentence 3, it describes the verb “spent”—it acts as an adverb; in Sentence 4, it describes the gerund “living”—it acts as an adjective.) In order to see whether either phrase is a basket, let’s try lifting it out:
3a. I spent most of my life.
4a. I made my living as a writer of fiction.
As you can see, 3a is an incomplete sentence—it’s missing something essential. We read it and think…”You spent your lifehow?” So the underlined phrase is essential to the sentence. It’s not a basket, and it should not be set off. Sentence 4a is okay. It works. The meaning is the same as Sentence 3—it’s just missing a bit of description, a bit of extra information implying that “my living” was rather austere. The underlined material is a basket and should be punctuated accordingly.
So: When trying to figure out whether to use setting-off commas, look for baskets.
Written by Jincy Kornhauser at Pearson Tutor Services