CommasThe primary use of this little piece of punctuation is to indicate a small break. Overuse will kill your story and make it difficult to read. You need a comma when there's a list, a direct address, or an introductory phrase. These are the three uses we'll be focusing on today. More uses of the comma will come later.
There are two ways to punctuate a list with commas. I'll give examples:
She debated with me over whether I should buy the green, white, or blue striped hat.
He went to the store for eggs, milk and bread.
In the first example, we've separated the items in the list with commas and used a comma before the conjunction. This is recommended by CMS. In the second example, we've omitted the last comma. Either way is correct as long as the style is used consistently. You may omit commas if every item is joined by a conjunction or if the last item is joined by an ampersand.
When using a direct address, commas go on either side of the name. Examples:
She looked up from her notebook. "Hey, Mom, what's for dinner tonight?"
As the speaker approached the podium, he could be heard talking to the attractive blonde. "You said your name was Myra? I have to say, Myra, I look forward to getting to know you."
Introductory phrases and words get commas unless the phrase is an introductory adverbial or participial phrase immediately preceding the verb it modifies. Words like: Oh (unless spoken), Ah, Well, Okay, Yes, and No get commas.
Introductory phrases -
After looking through the book, she dropped her head into her hands.
Peeking out from behind his mother's skirts was the boy we'd been searching for.
Introductory words -
Yes, we can go to the park today.
Okay, I'll see what I can do about that.
No, we won't be donating to your charity this year.
Keep in mind that it's perfectly okay to use two independent clauses with a conjunction and omit the comma. As long as the two clauses aren't particularly long, leaving the comma out is a good idea. It changes up your writing and keeps the reader engaged in the words on the page.
We'll go into more with another comma post Monday.
Well, that's all for today, folks! Until next time, WRITE ON!