Other Comma Rules PUNCTUATION LESSON

Review of Previous Rules To separate independent clauses when they are joined by any of the FANBOYS conjunctions To separate three or more words, phrases, or clauses written in a series To separate two or more coordinate adjectives that describe the same noun. [Coordinate adjectives are of equal importance.] To set off all geographical names and addresses To set off all items in dates (except the month and day) and titles in names. Before or after a quote or dialogue to separate the quote from the speaker

Commas Rule 7: After introductory elements Use commas after introductory a) clauses, b) phrases, or c) words that come before the main clause. While I was eating, the cat scratched at the door. Having finished the test, he left the room. Well, perhaps he meant no harm.

Commas Rule 8: For a big pause Use a comma near the end of a sentence to indicate a distinct pause or shift. He was merely ignorant, not stupid. You're one of the senator's close friends, aren't you? The speaker seemed innocent, even gullible.

Commas Rule 9: To set off Use commas to set off phrases at end of the sentence that refer back to an earlier part of the sentence. I scowled at the driver, who was driving recklessly down the road. Nancy waved enthusiastically at the docking ship, laughing joyously.  Lisa waved at Nancy, who was laughing joyously.  Kind of like an afterthought

Commas Rule 10: To prevent confusion Use commas wherever necessary to prevent possible confusion or misreading. YES: To George, Harrison had been a sort of idol. NO: To George Harrison had been a sort of idol.

What not to do with commas (1) Don't put a comma before a conjunction when there is not a complete thought before or after the conjunction. INCORRECT: We laid out our music and snacks, and began to study. INCORRECT: I turned the corner, and ran smack into a patrol car. INCORRECT: The music teacher from your high school, and the football coach from mine are married. INCORRECT: Jeff told me that the job was still available, and that the manager wanted to interview me. Don't put a comma after the main clause when a dependent (subordinate) clause follows it INCORRECT: The cat scratched at the door, while I was eating.

What not to do with commas (2) Don't use a comma to separate the subject from the verb. INCORRECT: An eighteen-year old in California, is now considered an adult. INCORRECT: The most important attribute of a ball player, is quick reflex actions. Don't put a comma in the middle of two independent clauses by itself. This is called a Comma Splice. INCORRECT: The key to winning the game is speed, I have been practicing all year. INCORRECT: Laughter can be very contagious, my friend makes me laugh whenever he does.

Source https://owl.english.purdue.edu/owl/owlprint/607/