Using the Comma

"Commas in The New Yorker fall with the precision of knives in a circus act, outlining the victim."

E. B. Whiteo

E. B. White's comment about the English language's most misused punctuation mark is a good way of thinking about how to use the comma. Use it precisely to set off what needs to be set off in a sentence to clarify, to emphasize, to separate, to group together, or to direct elements in the body of the sentence. As you will notice from your writing, commas can work like knives since to misuse a comma may "kill" your meaning and create a victim rather than outlining it.

Below are some common rules for using the comma. However, keep in mind that no rules are without exceptions. The best idea for determining when to use a comma is that if you cannot give a reason for using it--a reason based on a rule or a particular stylistic need--then don't use a comma.

Remember that comma rules are not intended to confuse you or make your life difficult; they are intended to help you make your writing clearer.

1. Use a comma after an introductory word, phrase, or clause.

Ex. A, introductory word:

Therefore, we need to move ahead to find peace.

Explanation: The comma emphasizes the word therefore by forcing readers to pause slightly after it.

Exception: Unless you want to emphasize that opening word (or it is a noun of direct address), do not use a comma.

Therefore you should not despair.

Explanation: A pause here would break up the short sentence and is unnecessary for emphasis.

However: Always put a comma after a noun of direct address that begins a sentence.

Celia, you can cast your move over there.

Ex. B, introductory phrase:

Finding no reason to stay home, Clara went to the nearest restaurant for dinner.

Ex. C, introductory clause:

Because Sharon and David Wessels were concerned about school loans, they decided to bank their money for the future.

 Explanation: The comma sets off the introductory dependent clause that serves to describe they. As you will notice from your reading and writing, when a clause begins with a subordinate conjunction, it nearly always is followed by a comma.

Ex. D, noun of direct address:

Kevin, don't forget to be here on November 22.

 

2. Use a comma before a coordinating conjunction (and, but, or, so, yet, for) to link two independent clauses.

 

 Ex. A, and:       

He believed in finding a healthy daycare for his children, and he was determined to search for it.

Ex. B, but:  

Hansen was a war hero, but her record wasn't clear about the details.

Ex. C, or:

We need to believe in miracles, or our country may not preserve its democratic institutions.

Ex. D, so:

America needs to save on energy, so everyone must do her or his part.

Ex. E, yet:

I was anxious to get a hunting license, yet I wasn't sure about the process.

Ex. F, for:

David hired Susan Whaley, for she was definitely the best choice.

Caution: A comma is not always used before every coordinating conjunction. Use the comma before coordinating conjunctions that separate independent clauses. Do not normally use the comma before coordinating conjunctions that connect two words, two phrases, or two dependent clauses. The arrows indicate the compounds that would not require commas. See Rule 1 in Unnecessary Commas.

 

3. Use commas to separate three or more items in a series of words, phrases, or clauses. It is preferred that you use a comma before the conjunction that connects the last item to the series.

Ex. A, words :                                      

To prepare for the lecture, Dr. Placedo read Thomas Jefferson, Thomas Paine, and Mary Wollstonecraft.

Notice: Both the first and last names of a person constitute a word.

Ex. B, phrases:

To insure a fairness, the test monitors moved the testing sites to public buildings, installed electronic monitors, and made sure the tests were handed out individually.             

Ex. C, clauses:

Local reforms were made necessary by the 2004 budget crisis when legislatures cut income taxes, enrollments declined, and some schools had to cut academic programs.

        

4. Use a comma to separate two or more adjectives that modify a noun individually.

Ex. A: Finding an honest, intelligent leader has been impossible.

Explanation: Both honest and intelligent describe candidate individually. If the comma were omitted, the sentence would mean that finding an intelligent candidate who is honest is difficult. The implication is that intelligent candidates are not always honest.

Ex. B: Senator Belleview tried her best to produce well-written, pertinent legislation.

Ex. C: A unified, educated military is necessary for our country's security.

 

5. Use commas to separate non-restrictive words, phrases, or clauses from the rest of the clause.

Ex. A: Governor Kelly, who earned her degree from South Dakota State University, vetoed the bill that outlawed gay marriages.

Explanation: The information who earned her degree from South  Dakota State University  is not essential to the meaning of the main clause; in other words, it can be omitted without changing the basic meaning of the sentence. However, it does add information about Kelly, and its use in the sentence is to indicate that it is relevant to her veto of the bill.

Ex. B: George Havers, philanthropist, did not plan on contributing to the new hate group.

Ex. C: Elinor Camp, sitting as the Third District Representative, has been both an entrepreneurial business owner and an electric engineer for General Electric.

Ex. D: Any legislation to raise taxes to support education will not be supported by David Leev transcendentalist and free-thinker.

 

6. Use a comma to set off mild interjections that begin a sentence.

Ex. A: Oh, I didn't know that he had dropped out of the program.

Ex. B: Well, I didn't have the time or the inclination to sit through the lecture.

Ex. C: No, I do not necessarily believe that a democracy is the best form of government.

Ex. D: OK, I know that I am not a taxpayer and have no right to complain about the roads.

 

7. Use commas to set off parenthetical elements, transitional devices, and conjunctive adverbs that occur within a clause. Put a comma before these phrases: such as or as in. Never put a comma after those phrases.

Ex. A, parenthetical element: Skydiving for the first time is a thrill, isn't it?

Ex. B, parenthetical element: Negative campaigning, not clear statements of the issues, makes candidates successful.

Ex. C, transitional devices: Terry Hale, for example., was not successful because he insisted on taking shortcuts.

Ex. D, transitional devices: The test outcome, however, was still in doubt.

Ex. E, conjunctive adverb: Leslie Feder is playing a strong game at right tackle; therefore, he is likely to be named player of the game.

 F, conjunctive adverb: The last game was not played cleanly; for instance, Carl Roove bought had lubricant in his pitching glove.

Ex. G, such as: Coffee ads, such as those produced by coffee growers, are usually exaggerations or even lies.

Ex. H,  as in: Some advertisers resort to clichÚs rather than facts, as in "It's better than ever."

8. Use comma to set off direct quotations. Put the comma inside the quotation marks when it is used to separate the quotation from the explanatory words about the speaker. Put the comma after the explanatory words and before the quotation marks when they lead into a quotation.

Ex. A: "When Americans go to war, they need to be prepared," declared the history professor.

Ex. B: Ms. Anderson spoke out, "Never forget that you do have a choice in how your country is run."

Ex. C: "We have a responsibility to our children," said Carroll, "to leave them without a serious debt."

Caution: Do not use a comma if the direct quotation ends with a question mark or quotation mark. Also do not use a comma if the direct quotation is used to complete a clause beginning with that. Do not separate a paraphrase from the explanatory words with a comma.

Ex. A: "Don't jump!" chanted the crowd.

Ex. B: Sybil asked, "If we suffer from multiple personalities, can we vote more than once?"

Ex. C: The 26th Amendment says that "The right of citizens of the United States, who are eighteen years of age or older, to vote shall not be denied or abridged by the United Sates or by any State on account of age."

Ex. D: According to the 26th Amendment, states cannot prevent any citizen who is eighteen years old or older from voting.

 

9. Use commas in names, addresses, numbers, dates, and titles. Notice that you put a comma both before and after states and years when they are used with other information in the middle of the sentence.

Ex. A: Robert F. Kennedy, Jr., has become an important spokesperson for the environment.

Ex.  B: Please pick up the senior citizens at Heritage Place, 104 East Lincoln, Constitution, Rhode Island, so that they can attend the meeting on social security reform.

Ex.  C: Gore had 50,999,897 votes to Bush's 50,456,002 votes in 2000.

Ex.  D: This year's Thanksgiving is on November 25, 2004, throughout the United States and its territories.

Ex. E: Susan Carrenden, PhD., has made it clear that she will not accept any late reports.

Caution: Do not use a comma to separate months and years when no specific day is given or when using the day-month-year order.

Ex. A: In October 1987, the United States economy was severely affected by collapses in  American Savings and Loans companies.

Ex. B: The Berlin Wall fell on 9 November 1989.

 

Unnecessary Commas

1. Do not use a comma to separate compound items joined by and.

Ex. A:

Incorrect: The country selected, and supported the worst candidate for the job.

Correct: The country selected, and supported the worst candidate for the job.

Explanation: Do not separate a subject from its second verb with a comma; therefore, do not put a comma before the and since doing so would separate the subject party from its second verb supported.

Ex. B:

Incorrect: She campaigned thoroughly for reforms, and her personal interests.

Correct: She campaigned thoroughly for reforms and her personal interests.

Ex. C:

Incorrect: She won the election because she was the best campaigner, and she supported increases for education funding.

Correct: She won the election because she was the best campaigner and she supported increases for education funding.

Explanation: Both of the dependent clauses are made dependent because of the single word because. Therefore they are compound dependent clauses and do not take a comma before the and.

 

2. Do not use a comma between a verb and its complement.

Ex.  A:

Incorrect: She grabbed her papers and went, into the meeting.

Correct: She grabbed her papers and went into the meeting.

Explanation: Rarely will you ever put a comma before a preposition. Do so only to emphasize the prepositional phrase or to avoid misreading.

Ex.  B:

Incorrect: Since coming to the United States and becoming a citizen, Safira has never failed, to vote in an election.

Correct: Since coming to the United States and becoming a citizen, Safira has never failed to voted in an election.

Ex.  C:

Incorrect: For her final act, she selected, the large gray elephant.

Correct: For her final act, she selected the large gray elephant.

 

3. Do not use a comma between the subject and verb, except when two commas are necessary to mark nonrestrictive sentence elements.

Ex.  A:

Incorrect: The 2004 baseball season, has gone on forever.

Correct: The 2004 baseball season has gone on forever.

Explanation: Do not put a comma between the subject of the sentence election and the verb has gone. The prepositional phrase for President is necessary to the sentence.

Ex.  B:

Incorrect: Cheryl Berger who finally took over the lead in the race, never faltered in her stride or determination.

Correct: Cheryl Berger who finally took over the lead in the race never faltered in her stride or determination.

Explanation: Although the clause when she finally took over the lead in the polls is long, a comma would separate the subject Cheryl Berger from the verb questioned.

Ex.  C:

Incorrect: Joan Barlow's campaign for Senate, which took place while she was also running for President meant that she had to spend more time in her state than on the regular campaign trail throughout the entire country.

Correct: Joan Barlow's campaign for Senate, which took place while she was also running for President, meant that she had to spend more time in her state than on the regular campaign trail throughout the entire country.

Explanation: The non-restrictive clause which took place while she was also running for President needs to be separated with two commas not one. A single comma only creates the punctuation error of separation of the subject campaign from the verb meant. Thus, you will never have a single comma between the subject and verb in any clause.

 

4. Do not use a comma before prepositional phrases, subordinate conjunctions, or other modifiers--unless they are necessary for clarification.

Ex. A:

Incorrect: Because Joseph and Larry didn't know anything about the issues, they gave their votes, to the candidate whom they felt had a good personality.

Correct: Because Joseph and Larry didn't know anything about the issues, they gave their votes, to the candidate whom they felt had a good personality.

Explanation: Although to the candidate whom they felt had a good personality is a lengthy prepositional phrase, it should not be preceded by a comma because the phrase is necessary to the sentence's meaning.

Ex. B:

Incorrect: Joanna and Mary registered to vote, after they realized, that voting was a privilege, that they could lose.

Incorrect: Joanna and Mary registered to vote after they realized that voting was a privilege that they could lose.

Explanation: The above example contains three subordinate clauses: 1) after they realized, 2) that voting was a privilege, and 3) that they could lose. All three clauses are necessary descriptors and, therefore, should not be separated from the sentence with commas.

Ex. C:

Incorrect: The candidates moved, carefully, into the, slow-moving crowd.

Correct: The candidates moved carefully into the slow-moving crowd.

Explanation: The modifier carefully describes how the candidates moved, and the prepositional phrase into the slow-moving crowd describes where the candidates moved. Never put a comma after the words a, an, or the.

oColumbia World of Quotations, 1996, Columbia, University Press.

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