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LAB 206
Using Commas and Semicolons
Overview: Some writers mistakenly use commas and semi-colons interchangeably, but they have very different functions
in English sentences. In order to understand the rules that govern commas and semi-colons, you’ll need to understand
some basic grammar terms.
Key Terms used in this discussion:
Clause: a group of words that contains a subject and a verb.
An Independent Clause is a complete thought and makes sense on its own.
Example: I already ate lunch.
A Dependent Clause contains a subject and verb, but it is an incomplete thought; it doesn’t stand alone.
Example: Although I already ate lunch
Phrase: a group of words that isn’t a clause; it’s missing the subject, the verb, or both, so it’s an incomplete thought.
Example: with my aunt and uncle
Example: running down the hall
Complete Sentence: must contain at least one independent clause so that the sentence makes a complete thought.
Commas are used in two main ways: to separate or to enclose elements of sentences.
Using Commas to Separate:
1. Use a comma to separate an introductory word (*), a phrase (**), or a dependent clause (***) from the independent
clause that follows.
*
Oh, I didn’t see you standing there.
*
Donna, did you steal that from my closet?
** Seeing me across the room, she smiled and waved.
** The game having ended, we went home.
*** Although she saw me across the room, she did not smile or wave.
*** Because she loved spinach, she ate his.
Practice:
A. Yes I’m going to the party tonight.
B. Unfortunately I had to stay up all night to study.
C. Glancing around nervously he stepped quickly into the alley and disappeared from view.
D. After you took lessons you became a much better singer.
2. Use a comma to separate two independent clauses joined with a coordinating conjunction (often called the
“FANBOYS”: for, and, nor, but, or, yet, so).
A. I was planning to come, but I changed my mind.
B. I went to Europe last fall, and my sister came with me.
You do not need a comma every time you use a conjunction. If you write, “I ate toast and jam for breakfast,” no
comma is needed because the “and” does not join two complete sentences.
Practice: Which sentence below needs a comma?
A. Chicago was too far away so we decided to fly.
B. I think you should cut your hair but not too short.
Copyright (C) 2016. All rights reserved. This handout is part of a library of instructional materials used in California State University, Long Beach’s writing
center, the Writer's Resource Lab. Educators and students are welcome to distribute copies as long as they do so with attribution to all organizations and
authors. Commercial distribution is prohibited.
3. Use a comma to separate words, phrases, or clauses in a series.
A. The house was huge, cold, and vacant.
B. We went to the mall, we watched a movie, and we made out in the back row.
Practice: He stood in the middle of the street smiling broadly full of life naked as a baby.
4. Use a comma to separate dialogue from the rest of the sentence.
A. I asked, “Donna, did you study for the test?”
B. “I did study for the test,” she replied.
Practice:
A. Debbie said “You look marvelous.”
B. “Put on a coat” yelled my mother as I ran out the door.
5. Use commas to separate two or more adjectives that come before the noun they modify when the adjectives are
coordinate. Adjectives are coordinate when each refers directly to the noun. That rule may be hard to understand, so
here’s a good test you can use to find out whether adjectives are coordinate. Rearrange the order of the adjectives. If the
sentence still makes sense, the adjectives are probably coordinate and should be separated with commas.
A. The slimy, wet, hissing snake coiled around his throat.
Rearranged: The hissing, slimy, wet snake coiled around his throat.
The rearranged adjectives make sense, so the adjectives are coordinate and should be separated with commas.
B. The small summer house was a romantic place to honeymoon.
Rearranged: The summer small house was a romantic place to honeymoon.
The rearrangement does not make sense, so the adjectives should not be separated with commas.
Practice: Which sentence below needs commas between the adjectives?
A. The garage was always hot smelly and messy.
B. The old high school is about to be torn down.
6. Use a comma to separate a sharply contrasted element near the end from the rest of the sentence.
A. He left already, didn’t he?
B. I asked for milk, not water.
Practice: The sentence below needs two commas, one based on rule #1 and one based on rule #6.
A. When we left for the mall she was still in bed wasn’t she?
7. Use a comma to separate free modifiers at the end from the rest of the sentence. They often begin with an “ing” or
“ed” word. (Free modifiers can also be moved to other places in the sentence.)
A. Maria ran to get her coat, smiling with excitement at the day ahead of her.
B. Maria ran to get her coat, excited at the prospect of going to Disneyland.
Practice:
A. Henry looked her in the eyes and smiled hoping she would not guess he was lying.
Using Commas to Enclose:
1. Use commas to enclose a name, word, phrase, or clause that functions as a non-essential interrupter in a
sentence.
A. I asked, Donna, whether you have studied for the test.
B. Your test results, however, indicate that you did not study.
C. Your parents, pleased with your grades, are sending you to Florida for Spring Break.
D. My car, the one that has a big dent in the door, was hit by a garbage truck yesterday.
(Note: In this sentence, I asked, Donna, whether you have studied for the test, the commas indicate that the speaker is
Copyright (C) 2016. All rights reserved. This handout is part of a library of instructional materials used in California State University, Long Beach’s writing
center, the Writer's Resource Lab. Educators and students are welcome to distribute copies as long as they do so with attribution to all organizations and
authors. Commercial distribution is prohibited.
talking to Donna. Without the commas, I asked Donna whether you have studied for the test, the sentence means that
“I” is talking to “you” about asking Donna.)
2. Do not put commas around essential interrupters. In the following sentences, the material that interrupts the subject
and verb is essential because it identifies which guy or which kitten is being discussed.
E. That guy wearing the black jeans asked me out.
F. The kitten with the black spots is my favorite.
Practice: Which sentence below needs commas around the interrupting words?
A. The new school which we painted red last week is in the middle of town.
B. The puppy that licked my hand is the same one who pooped on the carpet.
3. Use commas to enclose dates and addresses.
A. June 10, 1977, is his birthday. (Don’t use commas if you omit the day: He was born in June 1977.)
B. She was born in Portland, Maine, but she grew up in Eugene, Oregon.
Using Semi-Colons: Semi-colons are used in two main ways
1. Between two complete sentences:
A. I kicked the dog; the dog bit me.
B. I did study for the test; however, I failed it anyway.
In Example B, the semi-colon is used with a comma to enclose a transition word that joins two complete sentences.
(Note: Commas are used to enclose however when it acts as an interrupter in a single sentence (e.g. Your test results,
however, indicate that you did not study), but a comma and a semi-colon are used to enclose however when it acts as
a transition word between two complete sentences (e.g. I did study for the test; however, I failed it anyway). The
same rules apply to similar words and phrases, such as therefore, thus, consequently, as a result.)
Practice: Which example below needs a semi-colon and a comma? Which needs two commas?
A. I think you should cut your hair furthermore I think you should dye it purple.
B. You look good in black. Your sister however does not.
2. To separate elements in a list that already contains commas:
A. She has lived in Boise, Idaho; Walnut Creek, California; and Los Angeles, California.
B. Juan lives with his mother, a high-school teacher; his father, an attorney; and his sister, a student.
Practice:
A. When I was in college, I roomed with Cindy who is now a pilot for Alaska Airlines Suzanne who is
now a park ranger and Kathy who is now a mother of triplets.
Practice: It’s difficult to remember all of the comma rules at once. Here is one way to learn them. Choose one of the
comma rules that you have trouble remembering. Then, choose a paragraph or two from one of your current writing
assignments. Read through the paragraphs out loud, looking for places where you need to apply that rule. For example,
read through the paragraphs to see whether you need to add a comma where you’ve joined two sentences with one of the
FANBOYS. If you don’t find any sentences fitting that pattern, write one or two. When that rule becomes easy to
remember, choose another rule and practice that one. With a little practice, you won’t have to struggle to remember the
rules because putting commas in the correct places will come naturally to you. 
Copyright (C) 2016. All rights reserved. This handout is part of a library of instructional materials used in California State University, Long Beach’s writing
center, the Writer's Resource Lab. Educators and students are welcome to distribute copies as long as they do so with attribution to all organizations and
authors. Commercial distribution is prohibited.