Using Commas to Enclose

Nonessential Modifiers | Nonessential Appositives | Interruptions | Exercises

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Commas with Nonessential Modifiers

If you can remove a modifier from a sentence without changing the meaning of a sentence, then it is a nonessential modifier. Only nouns can have nonessential modifiers. These modifiers may provide interesting information about their respective nouns, but your sentence will function just as well without them. For example:

The reclusive author, who seldom even allows himself to be photographed , gave a surprisingly open interview to Rolling Stone.

The phrase “who seldom even allows himself to be photographed” gives extra information that may or may not be of interest to our reader, but it can be removed from the sentence without changing the meaning. Therefore, it should be enclosed by commas.

Commas with Nonessential Appositives

An appositive is a noun or noun phrase that modifies another noun or pronoun. These are almost always nonessential. For example:

Mark Twain, author of Huck Finn , is America’s greatest humorist.

While “author of Huck Finn” is useful information, especially for anyone who has never read Mark Twain, it can be removed from the sentence without altering the meaning. As such, it should be enclosed by commas.

Commas with Interruptions

When inserting interruptions in sentences that do not fall under the heading of modifiers or appositives—like contrast words, commentary, or when directly addressing someone—the interruption should be enclosed by commas. For example:

Please, sir, may I have another?

I could not, in good conscience, take money from my grandmother for mowing her lawn.

I could, however, take a few of her magnificent Snickerdoodles.

Once again, these interrupters all perform a function in their respective sentences, but none of them are so essential that they cannot be removed. Ergo, they should be enclosed by commas.

Exercises

Commas that enclose interactive exercises
Commas that enclose printable exercise

Questions
If you have any questions, please contact the Writing Center.