Commas: They're Not Just For English Majors Anymore.
Review

Okay, those are the big five.

Now for a quick review:

  • First, remember what we said at the beginning: you must justify each comma you use. If you don't have a specific reason for using a comma, you probably don't want it there.
  • Second, remember the big five reasons for using commas we've covered:
Don't Forget!
 
YOU MUST HAVE A REASON FOR EACH COMMA YOU USE.

Use commas with...

IE - Introductory Elements
An introductory element is a word, phrase, or clause before the main part of the sentence. It usually tells us something about the main clause.

  • If we cannot control our tempers, we may have to bite those mimes.
  • On the other hand, they may bite us first.
CE - Contrasting Elements
Use commas to set up the contrast. Key words: but, yet, not, never, although
    Wilma, not Betty, has a necklace made of rocks.
21C - Two Independent Clauses
(a.k.a. "compound sentences") When two independent clauses are joined with a coordinating (and not any other kind of) conjunction, place a comma before the conjunction.
(Remember: FANBOYS!)
    The Misfit takes the son's shirt, and he shoots the grandmother.
CA - Compound (or Coordinate) Adjectives
Use commas to separate consecutive adjectives:
    The closet was full of old, worn clothes.
Do not, however, use a comma when the order of the adjectives matters (i.e., when you can't simply reverse them without seriously changing the meaning):
We were suspicious of the fried green tomatoes. 
(After all, fried green tomatoes may taste good, but green fried tomatoes might make you sick).

NRE - Non-Restrictive Elements
These elements are the ones known, often misleadingly, as "the part you could just take out": parenthetical comments, direct address, appositives, transitional words and phrases, etc. 

    The pressure of being a clown was enough, it seems, to make even a brave man weep.
They can also appear at the end of a sentence:
He wanted to run into the airplane propeller, an act that would have dramatically shortened his life expectancy.
next (a few other situations)

Intro, Get Started, IE, CE, 2IC, FANBOYS, CA, NRE, Review

IE: Introductory Elements
CE: Contrasting Elements
2IC: Two Independent Clauses
CA: Compound or Coordinate Adjectives
NRE: Non-Restrictive Elements
A Few Other Situations (quotations, lists, etc.)