Place a comma before a coordinating conjunction (and, or, but, nor, so, for, yet) joining two or more independent clauses.

Model sentence: I was going to go to the party, but I fell asleep while watching television.

Place a comma between all of the items in a list.

Model sentence: She shopped for paper plates, napkins, cups, and plastic spoons.

Place a comma directly after tags or phrases preceding direct quotations.

Model sentence: The author of the best-selling novel declared, “I can’t wait to start working on my next book.”

Place a comma between dates, addresses, and titles:

Model sentence: Robert Smith, PhD, received his doctoral degree on May 14, 2007.

Set off nonrestrictive appositives and nonessential phrases and clauses by placing a comma on both sides. (Do not use commas with restrictive appositives such as the poet Robert Frost.)

Model sentence: Will’s girlfriend, Halle [nonrestrictive appositive], whom he has dated for two years [nonessential clause], doesn’t know how to drive.

Place a comma directly after conjunctive adverbs and transitional phrases, such as however, also, then, therefore, for instance, in conclusion, in fact, and for example.

Model sentence: In fact, the black shoes are handcrafted in Italy.

Use a comma after an introductory adverbial clause or a prepositional phrase.

Model sentence: Under the decaying front porch, we discovered a box filled with books and old letters.

Place a comma within (before) the end quotation mark of a direct quote preceding a tag (unless the quote ends with a question mark or an exclamation point).

Model sentence: “I’m going on vacation next week,” said Tanya.