The appendage comma separates embellishing and explanatory information from the main thought of a sentence. Generally, these supplemental details could be deleted without losing the sentence’s essential meaning. Like arms, however, appended information can be very useful:

Appendages: Lesson One

Vocatives

USE THE COMMA

✓ In sentences:
Cake, how could you?

✓ In salutations:
Hi, James,

DON’T USE THE COMMA

✗ With verbal subjects or objects:
I’m taking the dogs to the park with Emma.

Appendages: Lesson Two

Interjections

USE THE COMMA

✓ With mild interjections:
That, alas, was the last bite of chocolate.

✓ With verbal pauses:
I, um, sorta broke your laptop.

Appendages: Lesson Three

Peripheral Remarks

USE THE COMMA

✓ With short parenthetical comments:
That meal could have used ketchup, to say it kindly.

✓ With rhetorical or leading question tags:
That wasn’t so bad, was it?
I know, right?

Appendages: Lesson Four

Linking Adverbs

USE THE COMMA

✓ With linking adverbs:
Emilio can’t decide. I, however, approve.

DON’T USE THE COMMA

✗ After a coordinating conjunction that starts a sentence:
I’ve no idea what Emilio will choose. But I approve.

Appendages: Lesson Five

Attribution Tags

USE THE COMMA

✓ With quotation attribution tags:
“No hurry,” she said, “but right now would be great.”

✓ With source attribution tags:
Andrea, according to her assistant, will attend the conference.

✓ With psychological attribution tags:
It didn’t matter, Sheila decided.

DON’T USE THE COMMA

✗ With tags that follow quoted question or exclamation marks:
“Why aren’t you hurrying?” she asked.

✗ With conjuncted attributions or running quotations:
He saw his children as “cloud shadows crawling over mountains—the evidence of something bigger.”

Appendages: Lesson Six

Nonrestrictives

USE THE COMMA

✓ With professional name suffixes and nonrestrictive titles:
Adina Jamal, M.D., Director of Cancer Research

✓ With nested location names:
Dallas, Texas, United States of America

✓ With nonrestrictive appositives:
Have you met my gray cat, Ash?

✓ With nonrestrictive dependent clauses:
Chanel has moved to the Philippines, since she wants to study emerging economies.

✓ With descriptive reiterations:
They fled, sprinting like gazelles.

DON’T USE THE COMMA

✗ With personal name suffixes or restrictive titles:
Yes, I’ve met your gray cat Ash. He scratched me.

✗ With restrictive appositives:
Dr. Benjamin Covington Jr.

✗ With restrictive dependent clauses:
Chanel’s luggage that held most of her notes was lost during a layover.

The Structure Comma

Unit Three Overview

The structure comma helps readers identify how the essential elements of a sentence are arranged and relate to each other. The comma can also indicate the arrangement of longer sentence appendages.