Comma Rules:

“The least you need to know”

Commas in a Series

Kate purchased clothes, a suitcase, and a one way ticket to Oregon. 

(Separate three or more items with commas.)

Kate purchased a wide variety of clothes from Hollister and Hot Topic; a genuine Coach suitcase from the Wrentham Outlet store; and a one way ticket to her family’s hunting lodge in Oregon.

(Use a semicolon when the items in the series are longer.)

Commas in Compound Sentences:

Harry drove the getaway car, and Jack was arrested for robbing his favorite tattoo parlor. 

(Each side of the conjunction can be its own sentence, so a comma is needed before the conjunction to give the speaker a chance to breathe.)

Harry drove the getaway car and Jack was arrested.

 (Here the comma is not needed because even though we are joining two complete sentences with a conjunction, one side is too short to for a speaker to need time to breathe.)

Comma Usage in Appositives:  “The Rumor Rule”

Herman, the kid with buck teeth, was dating the prom queen.

(See here how “The kid with buck teeth” looks like it could be in parenthesis?  In English we prefer to use commas instead of parenthesis.  Notice how an appositive is added information about the noun before it.)

Comma Usage in Nouns of Direct Address:
(Here we are directly talking to Quinton, not just about him. Notice where the commas occur when you place his name at the beginning, the middle, or the end of a sentence.)

John, where on Earth did you get that thing?

Where on Earth, John, did you get that thing?

Where on Earth did you get that thing, John?

Comma Usage in Introductory Words:
(These are at the start of a sentence.)

Yes, I will have some more cake.

By the way, I love Hearth and Kettle’s chocolate cake.

Comma Usage in Interrupters:

(The same words that can be Introductory words, but they are placed in the middle of a sentence.)

I love, by the way, Hearth and Kettle’s chocolate cake.

Comma Usage with Two Adjectives and the Exception:

It was a long, cold night for the contestant on Survivor.

(Here “long” and “cold” are adjectives describing the noun “night”.  The exception is when one of the adjectives is an article.  Remember those articles- “A”, “An”, and “The”.

Comma Usage in Dates and Addresses:

April 23, 1616, was the day Shakespeare died.

(Comma needed between the day and the year.  Comma needed after the date because the sentence continues.  This rule is debatable: some would argue that it is too short.)

A bill from 1313 Mockingbird Lane, Hyannis, MA 02601, came in the mail today.
(Comma needed between the street and the town.  Comma needed between the town and the two-letter state abbreviation.  Comma needed after the zip code because the sentence continues.  Again, some people disagree with this practice.)

The notice was given in May 2006.

(No commas are needed between the month and year.

Comma Usage in Letter Parts/ Salutations:

Dear Colleen,

Love always,

To Mr. Clark,

(A colon could also be used to look more formal.)