1) Use commas after the parts of a complete address in a sentence.  The house number and street form one part, as do the state and ZIP code number.  Of course, put commas between the city and the state, and put no commas between the state and the ZIP code. (put commas at the end of each line on an envelope).

Ex. The store manager asked her new assistant to send the hefty package to Dr. Alicia Raycroft, 4717 Bradford Street, Revere, Massachusetts 02151, today.

2) Use commas after the various parts of a complete date.  The month and the day form a single part.

Ex. On June 2, 1973, I went to California.    

Ex. On Thursday, April 5, 1956, we had a blizzard.

*EXCEPTION:  Use no comma after a date or an address that contains only one part—unless, of course, the comma is necessary for some other reason. (That happened in June of 1963.)

*EXCEPTION:  Also, use a period, not a comma, after the last part of a complete address or date that ends a sentence. (He left on June 20, 1999.)

3) Use a comma after the salutation and the complimentary close of a friendly letter and after the closing of a business letter.  (salutations in business letters are followed by colons instead of commas—To Whom It May Concern:)

Ex. Dear Susan, Yours affectionately,             Very truly yours,

4) Use a comma to set off a noun in direct address (someone you are directly addressing).

Ex. James, Mother wants you. (speaking to James) 

Ex. Turn off the lights, Jill.  (to Jill)

5) Use a comma to set off an appositive unless it is closely tied to the word it explains.

Ex. Dawn, my pony, is in the barn. (interchangeable; pause; not necessary) (*not necessary=commas)

*EXCEPTION: The year 1941 will always be remembered by Americans. (no pause; closely related—the year “1941” is necessary for the sentence’s meaning; without it, the reader asks, “What year?”) (*necessary=no commas)

6) Use a comma to set off the exact words of a speaker from the rest of the sentence—unless the sense of the sentence requires some other mark (?!).  Notice that end quotation marks come after the comma, not before (most punctuation comes within the “”).

Ex. “Why, yes,” Ellen answered, “I can help you now.” 

Ex. “What time is it?” she asked.

*EXCEPTION:  An indirect quotation needs no comma. (He said that Jane had left.)

7) Use commas to separate each item in a series of (3+) words, phrases, or short clauses. Do not forget the comma before the “and.”

Ex.  From Helen’s book dropped a pencil, a pen, and a stick of chewing gum.

Ex. We looked in the barn, in the cowshed, and in the corncrib.

Ex. Gladys has gone to town, Mary is asleep, and Nancy is jogging. (an exception to the RUN-ON RULE regarding no more than 2 independent clauses per sentence)

*EXCEPTION: Use no comma between two or more words that are usually thought of as a single item. (I like a picnic of hamburgers, pork and beans, and potato chips.)

*EXCEPTION: Use no comma in a series in which all the items are joined by “and” or “or.”  (Irma dances and sings and whistles very well.)

8) Use a comma before the coordinating conjunction that connects two independent clauses in a compound sentence. (“FAN BOYS”)

Ex. Bill should arrive today, but Alan will not be with him.

9) Use a comma to set off parenthetical elements; that is, words inserted between main sentence parts but not necessary to the meaning (and can thus be excised).

Ex. This story, by the way, is true. You will, of course, agree.

10) Use a comma after yes, no, oh, of course, well, and other such introductory expressions.

Ex. Yes, there is a test on this material.  Of course, you must study.

11) Use a comma after an introductory dependent clause.

         Ex. If you want to see that concert, order your tickets as soon as possible.

12) Use a comma after an introductory modifying phrase containing a participle (-ing, -ed), a gerund (-ing as noun), or an infinitive (to + verb).

Ex. Feeling warm, I drank a glass of lemonade.

Ex.  Bored with the lecture, Jackie fell asleep and missed vital information that was on the test.

13) Use a comma between co-ordinate adjectives before a noun

(2 adjectives modifying the same noun AND “and” sounds right when placed between them).

Ex. This has been a clear, sunny day. (clear and sunny)

Ex. Aunt Mary screamed, “Isn’t she such a cute little girl!” (not cute and little girl) (she's not cute AND vertically challenged.)

14) Use a comma to set off words that are added to change statements into questions or exclamatory sentences.

Ex. We are going to the game, aren’t we?      

Ex. We showed them, didn’t we! (exceptions to the COMMA SPLICE RULE regarding 2 independent clauses and a comma--here, separating statement from question and exclamation)