I have another minor obsession to confess, assuming you remember my obsession confession about singer Josh Groban in my first column. But this obsession is currently burning hot, and it’s with the hit Broadway musical “Hamilton.” I adore the entire show, from top to bottom, but there is one moment that especially appeals to me as a grammar enthusiast.

Early in Act 2, Alexander Hamilton is exchanging letters with his sister-in-law Angelica, and one of those letters addresses her as “My dearest, Angelica.” As she notes, the comma after dearest affects the meaning of the phrase. Without a comma, dearest would simply serve as a formal greeting. By inserting that comma, however, Alexander is implying that “Angelica” is his one and only dearest. The comma tells the reader that whatever is forthcoming, in this case Angelica, is not essential to the phrase, indicating she cannot be confused with anybody else. While I don’t condone using punctuation to flirt with your wife’s sister, I do appreciate this understanding and promotion of proper comma usage.

As this item in “Hamilton” demonstrates, commas can be used to set off nonessential information in a sentence. In other words, if a clause, phrase, or word is offset on both sides by commas, the sentence will make sense without it. If you’re referring to a person or thing by name, offset it with commas if it is the only person or thing to which you could be referring: “My wife, Eliza, … ” because you have only one wife, but “My son Philip …” if you have more than one son.

You should also use a comma before someone’s name in a direct address: “Happy birthday, Amanda.” On the other hand, you should not use a comma after a title that precedes someone’s name: It’s “President John Adams,” not “President, John Adams.” This is a common error.

Titles should only be set off with commas when they are after someone’s name. “She loves Josh Groban, celebrated crooner, who …”  is correct, but “She loves celebrated crooner, Josh Groban” is incorrect. This is another illustration of the nonessential information rule. If you removed “celebrated crooner” from the first sentence, it would still make sense, but if you removed “Josh Groban” from the second, it would not. In the second sentence, you are using celebrated crooner as an adjective to describe Mr. Groban, your noun. A sentence must have a noun.

If this idea trips you up, try remembering another general rule of commas: They initiate pause. You wouldn’t pause after someone’s title—think “Talking to Mayor Rahm Emanuel”—before saying the person’s name.

Commas are also used to indicate pauses after introductory clauses and phrases: “If I were a millionaire, I would buy myself some pet dolphins.” In compound sentences with two distinct subjects, commas are used before the conjunction to separate the clauses: “Hamilton is coming to Chicago this fall, and Amanda can’t wait.”

If you’re a grammar enthusiast, you may be wondering why I haven’t yet addressed everyone’s favorite punctuation controversy: the serial comma, also known as the Oxford comma. For the uninitiated, a serial comma is placed before the conjunction when you list items in a series. Why haven’t I taken a position in my column? Because I don’t really have one, if you can believe it.

AP Style says not to use a serial comma, because it is unnecessary, but other sources (including this magazine) go the other way because the comma is correct and formal. So, when it comes to the Oxford comma, please feel free to do whatever feels right to you. You know what else you should do? See “Hamilton” while it’s in Chicago. Have I mentioned I’m into “Hamilton”?

Amanda Jacobs is a grammar expert who worked at 22nd Century Media as editor and chief copy-editor for three years. She is currently a public relations specialist at the American Academy of Dermatology.

About the author

Amanda Jacobs is a grammar expert who worked at 22nd Century Media as chief copy editor and editor for three years. She is currently a public relations specialist at the American Academy of Dermatology.

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