1. Use this PowerPoint to fill in your foldable. Have fun!
Conquering the Comma
Rationale: Welcome to “Conquering the Comma.” This presentation is designed to acquaint your students with the rules of comma usage, including placement in compound sentences, after introductory elements, with dependent phrases and clauses, around nonessential elements, in a series, and with adjectives. This presentation will also cover methods for avoiding a common comma error—the comma splice. The twenty-seven slides presented here are designed to aid the facilitator in an interactive presentation of the elements of comma usage. This presentation is ideal for the beginning of a composition course, the assignment of a writing project, or as a refresher presentation for grammar usage.
This presentation may be supplemented with OWL handouts, including “Using Commas” ( “Commas after Introductions” ( and “Commas with Non-essential Elements” (
Directions: Each slide is activated by a single mouse click, unless otherwise noted in bold at the bottom of each notes page.
Writer and Designer: Jennifer Liethen Kunka
Contributors: Muriel Harris, Karen Bishop, Bryan Kopp, Matthew Mooney, David Neyhart, and Andrew Kunka
Developed with resources courtesy of the Purdue University Writing Lab
Grant funding courtesy of the Multimedia Instructional Development Center at Purdue University
© Copyright Purdue University, 2000.
Use this PowerPoint to fill in your foldable. Have fun!
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2. What Is a Comma?
A comma is a punctuation mark that indicates a pause is needed in a sentence.
Commas help to clarify meaning for the reader. ,
Key Concepts: The facilitator may choose to invite the audience to respond to the title question and allow participants to discuss the function of the comma. Many writers become frustrated with comma usage because they are unsure of where to place them in their sentences. This presentation is designed to demystify the placement and usage of commas.
The facilitator may stress to participants that commas should not be ignored in writing; they are often needed to clarify meaning within a sentence and can help to avoid confusion.
Click mouse after title question to reveal each response.
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3. Some Common Comma Rules
Key Concepts: This slide explains the structure of an independent clause, the primary building block for the development of any sentence. An independent clause requires a subject and a verb that can stand as a complete thought. Sentences can be very short, as the one detailed in the slide. The facilitator may ask the audience to identify the subject and verb in the example.
Click mouse after text appears to reveal picture and sample sentence.
Click mouse after sample sentence to reveal the labels “subject” and “verb.”
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4. Sentence Structure: Compound Sentence
The comma in a compound sentence is placed before the coordinating conjunction.
Andy built a snowman, and Jeff played with his dog.
S V conj.
Andy built a snowman, and
Jeff played with his dog.
S V
Example: This slide exemplifies the location of a comma in a compound sentence, before the coordinating conjunction. The facilitator may ask participants to identify the subjects, verbs, and conjunction in the example.
Click after example sentence appears to reveal parts of speech.
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5. Introductory clause= dependent clause located at the beginning of a sentence
When a dependent clause is placed at the beginning of a sentence, place a comma between the independent clause and the dependent clause.
Key Concepts: An introductory clause is a dependent clause located at the beginning of a sentence. After an introductory clause, a comma is needed to distinguish it from the independent clause.
Activity: The facilitator may choose to ask students to identify the independent and dependent clauses, the subjects, the verbs, and the dependent clause marker in the sample sentence.
Click mouse to reveal the parts of speech.
When Elizabeth called 911, the firemen rushed to her rescue.
When Elizabeth called 911, the firemen rushed to her rescue. DCM S V S V
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6. Where would you place the comma in the following examples?
Introductory Clause
Where would you place the comma in the following examples?
Since it was raining, we decided to go to the movies. DCM S V S V
Since it was raining we decided to go to the movies.
Once the movie began, I fell asleep.
DCM S V S V
Once the movie began I fell asleep.
Activity: This interactive slide invites participants to place commas after the introductory clauses in each sentence. Again, the facilitator may ask students to identify the parts of speech in each example.
Click mouse to reveal parts of speech, and then click again to reveal each example.
After the movie ended, we went out for coffee.
DCM S V S V
After the movie ended we went out for coffee.
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7. Dependent Clauses When a dependent clause is
located after an independent clause,
DO NOT place a comma between the two.
I went on the roller coaster because my brother dared me.
S V DCM S V
Activity: When a dependent clause follows an independent clause, commas are not used. Facilitators may choose to ask students to identify the parts of speech in each example.
I became very sick when the
S V DCM
roller coaster zoomed upside down.
S V
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8. Would you place commas in the following sentences? If so, where?
The place that I would most like to see is the Eiffel Tower.
Activity: These examples allow participants an opportunity to test their comma skills.
The first example needs a comma after “Paris” to set off the nonessential phrase.
The second example requires no comma. The phrase “that I would most like to see” is essential to the meaning of the sentence. The sentence will not make sense without this essential phrase.
The third example requires two commas, both before and after the nonessential phrase “who is one of my business contacts.” The main message of this sentence—that Pierre will meet this person at the airport—is clear without knowing the additional information about his identity.
Click to reveal the comma placement for each example.
No comma is needed. The sentence is correct.
Pierre, who is one of my business contacts, will meet me at the airport.
Pierre who is one of my business contacts will meet me at the airport.
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9. Sentence Structure: Commas in a Series
Place commas in a sentence to divide items in a list.
The commas will help the reader to avoid confusion.
The comma before the conjunction is generally required.
Key Concept: Commas should be placed between each element within a list. This placement can help the reader to avoid confusion.
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10. Sentence Structure: Commas in a Series
Commas should be placed in series of words, phrases, or clauses.
Place commas in the following sentences:
Martina brushed her hair, put on her pajamas, and went to bed.
Martina brushed her hair put on her pajamas and went to bed.
Activity: The facilitator may stress to participants that a series includes a list of words, but it can also include a list of phrases or clauses. This exercise allows participants to determine when the commas should be placed in each sentence.
Click to reveal commas for each sentence.
She fell asleep and dreamed that she was a princess, she kissed a frog, and she rescued her prince.
She fell asleep and dreamed that she was a princess she kissed a frog and she rescued her prince.
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11. Commas with adjectives
Use commas to separate adjectives that provide an equal description of a noun.
THE TEST:
Can you put “and” between the adjectives?
Can they be described in reverse order?
If so, use a comma.
Key Concepts: Students often find comma placement between adjectives to be tricky. The key is to determine if the adjectives are equal—meaning that they modify the noun in the same capacity. Adjectives of size and quantity are generally considered to be unequal to adjectives of character or quality. Placing “and” between adjectives or reversing the order of adjectives are good tests to determine if a comma is needed.
big blue house three hungry kittens
a cranky, ungrateful man
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12. A Common Comma Error: The Comma Splice
Copy this definition and one example on back of foldable.
A comma splice is an error in which two independent clauses are joined by a comma.
We had a nice time, I hope we can meet again soon.
S V S V
Key Concepts: One of the most prevalent comma errors is the comma splice—the placement of a comma between two independent clauses.
The Internet has revolutionized the business world,
S V
online sales have increased dramatically this year.
S V
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13. To Correct a Comma Splice
Insert a conjunction between the two independent clauses.
Start a new sentence.
Insert a semi-colon between the two independent clauses (only in cases where the independent clauses are closely related in topic).
Key Concepts: This slide enumerates several methods for correcting comma splices. The examples listed here are corrections of the comma splices in the previous slide.
We had a nice time, and I hope we can meet again soon.
We had a nice time. I hope we can meet again soon.
The Internet has revolutionized the business world; online sales have increased dramatically this year.
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14. How would you correct the following sentences?
This semester I am taking calculus physics and economics.
This semester I am taking calculus, physics, and economics.
Calculus is my best subject, I am certain I will get an A.
Calculus is my best subject, and I am certain I will get an A.
Although I am very busy, I still find time to have fun.
Although I am very busy I still find time to have fun.
Activity: This slide invites participants to again test their comma skills.
The first example requires commas between each element within the list.
The second example contains a comma splice. The sentence may be corrected by the addition of a conjunction after the comma, turning the comma splice into a compound sentence. This example may also be corrected by separating the two clauses into two separate sentences, or by changing the comma to a semi-colon.
The third example requires a comma after the introductory clause. The facilitator may wish to note that “although” is a dependent clause marker.
The fourth example, a compound sentence, requires a comma before the conjunction. Commas are also needed after each element in the list.
Click mouse to reveal comma placement for each example.
Last weekend my brother visited me, and we went to a football game, a party, and a rock concert.
Last weekend my brother visited me and we went to a football game a party and a rock concert.
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