1. Grammar: Commas Part 2

2. Rule 5
Use a comma to set off introductory elements or dependent clauses that introduce a sentence.
Examples:
Running toward third base, he suddenly realized how stupid he looked.
After his long nap in the backyard hammock, Figueroa felt better.
Exception: if the introductory phrase immediately precedes a verb no comma is used
Incorrect: Out of the dark, stepped the man in black.
Correct: Out of the dark stepped the man in black.

3. Rule 6
Use commas to set off the name, nickname, term of endearment, or title of a person directly addressed.
Examples:
Will you, Alisha, do that assignment for me?
Yes, old friend, I will.
Good day, Captain.
Jeff, will you take the dog outside for a walk?

4. Rule 7
Use commas to set off expressions that interrupt the sentence flow (nevertheless, after all, by the way, on the other hand, however, etc.).
The interruption can be taken out and the sentence still makes sense
Examples:
I am, by the way, very nervous about this.
The school year, on the other hand, was going by extremely fast.
The movie, in my opinion, was terrible.

5. Rule 8
In the preceding examples, note the comma after sister and late. Nonessential words and phrases that occur mid-sentence must be enclosed by commas. The closing comma is called an appositive comma. Many writers forget to add this important comma. Following are two instances of the need for an appositive comma with one or more nouns.
Incorrect: My best friend, Joe arrived.
Correct: My best friend, Joe, arrived.
Incorrect: The three items, a book, a pen, and paper were on the table.
Correct: The three items, a book, a pen, and paper, were on the table.
Use commas to set off nonessential words and phrases that add more description to the sentence.
Think to yourself: “Is the word or phrase necessary to understand the sentence?”
Incorrect: Jill who is my sister shut the door.
Correct: Jill, who is my sister, shut the door.
Incorrect: The man knowing it was late hurried home.
Correct: The man, knowing it was late, hurried home.