Comma Rules
*22f. Items in a Series
*22g. Separating Adjectives
*22h. Independent Clauses
*22i. Nonessential Clauses/Phrases
*22j. Introductory Elements
*22k. Interrupters
*22l. Conventional Uses
*22m. Unnecessary Commas
22f. Items in a Series
Use commas to separate items in a series.
EX: I like cheese, pepperoni, and sausage on my pizza.
Words customarily used in pairs are set off as one item
in a series.
EX: Sometimes I like to eat macaroni and cheese,
biscuits and gravy, or milk and cookies.
22g. Separating Adjectives
Use commas to separate 2+ adjectives preceding a
noun.
EX: For lunch we had smooth, creamy broccoli soup.
EX: Sally has a shiny, red bike.
NOTE: If a word modifies (describes) 1 of the
adjectives preceding the noun, the word is an adverb,
not an adjective, and therefore should not be followed
by a comma.
EX: Which of these neckties looks best with this light
green shirt? [Light modifies the adj. green, not the
noun shirt.]
22h. Independent Clauses
Use a comma before a FANBOYS when the
conjunction joins independent clauses (a compound
sentence).
EX: Charlie brought charcoal and lighter fluid, but he
forgot matches.
EX: Mary took her dog for a walk, but she skipped
going down Third Street to avoid the creepy cemetery.
22i. Nonessential Clauses &
Phrases
Use commas to set off nonessential subordinate clauses
and nonessential participial phrases.
*A nonessential (or nonrestrictive) subordinate clause
or participial phrase contains information that is not
necessary to the basic meaning of the sentence.
EX: Emilia Ortiz, who lives across the street from me,
won a scholarship to Stanford University.
[nonessential clause]
EX: Kelly, waiting outside the stage door, got the band
leader’s autograph.
*These clauses & phrases can be left out without changing
the main idea of the sentence.
22i. Nonessential Clauses &
Phrases
An essential (or restrictive) subordinate clause or
participial phrase is not set off by commas because it
contains information that is necessary to the meaning
of the sentence.
EX: The sophomores who made the Honor Roll were
listed in the school newspaper.
EX: Library books that are lost or damaged must be
replaced.
EX: Two poems written by Lorna Dee Cervantes are
included in our literature book.
22j. Introductory Elements
Use a comma after certain introductory elements.
1. Use a comma to set off a mild exclamation such as
well, oh, or why at the beginning of a sentence. Other
introductory words such as yes and no are also set off
by commas.
EX: Sure, I’ll go with you.
EX: Oh, look at that car!
EX: No, I haven’t taken the exam yet.
22j. Introductory Elements
2. Use a comma after an introductory participle or
participial phrase.
EX: Shivering, the couple hurried into the warm lobby
of the movie theater.
EX: Calling for a timeout, the referee blew his whistle
and signaled.
EX: Exhausted after a three-mile swim, Diana emerged
from the water.
22j. Introductory Elements
3. Use a comma after an introductory prepositional
phrase if the phrase is long or if 2+ phrases appear
together.
EX: During the long bus ride home, we sang songs
and told stories to amuse ourselves.
EX: By the light of the harvest moon in September, we
went on an old-fashioned hayride.
22j. Introductory Elements
4. Use a comma after an introductory adverb clause.
*An introductory adverb clause may appear at the
beginning of a sentence or before any independent
clause in the sentence.
EX: When you’ve gone to this school for a while,
you’ll know your way around, too.
EX: The first game of the season is Friday; after we
claim our first victory, we’ll celebrate at Darcy’s Deli.
22k. Interrupters
Use commas to set off an expression that interrupts a
sentence.
1. Use commas to set off nonessential appositives and
nonessential appositive phrases.
*An appositive is a noun/pronoun placed beside
another noun/pronoun to identify or describe it. An
appositive phrase consists of an appositive and its
modifiers.
EX: A senator from Kansas, Nancy Landon
Kassebaum, was the principal speaker.
EX: Do you know him, the boy wearing the blue shirt?
22k. Interrupters
A nonessential (or nonrestrictive) appositive or
appositive phrase adds information that is unnecessary
to the basic meaning of the sentence. In other words,
the meaning of the sentence is clear and complete with
or without the appositive or appositive phrase.
EX: Have you read At Home in India, a book by
Cynthia Bowles?
EX: On July 20, 1969, Neil Armstrong, one of the
three astronauts on the Apollo 11 mission, became the
first person to walk on the moon.
22k. Interrupters
An essential (or restrictive) appositive or appositive
phrase is not set off by commas because it adds
information that makes the noun/pronoun it
identifies or explains more specific. In other words, if
you were to omit an essential appositive or appositive
phrase, you would leave out key information or would
change the intended meaning of the sentence.
EX: My friend James helped me.
EX: Speaking of movies, have you seen the animated
film The Prince of Egypt?
22k. Interrupters
Use commas to set off words used in direct address.
EX: David, please close the door.
EX: Did you call me, Mother?
EX: Yes, Mr. Ramos, I turned in my paper.
22k. Interrupters
Use commas to set off parenthetical expressions.
*A parenthetical expression is a side remark that adds
information or shows a relationship between ideas.
EX: In fact, Emily Dickinson is my favorite poet.
EX: You are, I hope, planning to arrive on time.
After all
At any rate
Consequently
For example
For instance
Generally speaking
However
I believe
In fact
In the first place
Meanwhile
Moreover
Nevertheless
Of course
On the contrary
On the other hand
That is
Therefore
22l. Conventional Use
Use commas in certain conventional situations.
1. Use commas to separate items in dates and
addresses.
EX: On Saturday, June 21, 1999, Robert moved to
Miami Beach, Florida, with his parents.
EX: His new address is 814 Georgia Avenue, Miami
Beach, Fl 33139.
22l. Conventional Use
2. Use a comma after the salutation of a personal letter
and after the closing of any letter.
EX: Dear Marcus,
EX: Sincerely yours,
NOTE: Use a colon after the salutation of a business
letter.
EX: To whom it may concern:
22l. Conventional Use
3. Use a comma to set off an abbreviation, such as Jr.,
Sr., or M.D., that follows a person’s name.
EX: Elena Moreno, M.D.
EX: Russell E. Davis, Jr., has been elected mayor.
22m. Unnecessary Commas
Do not use unnecessary commas.
*Too many commas can be as confusing as too few. Do
not use a comma unless a rule requires one or unless
the meaning would be unclear without it.