The Comma

The comma serves many different purposes and is the most widely used of all punctuation marks. Because of its varied and distinct uses, it is also the most troublesome of the marks. And yet this mark of punctuation, more than any of the others, can and does help to make clear the meaning of writing. Its overuse and misuse also obscure meaning more than the mishandling of any other mark. If you can master even the basic uses of the comma--and you can--no other mark of punctuation can hold any terrors for you.

Always used within the sentence, the comma serves four purposes: to introduce, to separate, to enclose, and to show omission.

Before undertaking study of these four purposes of the comma, it may help you to consider ten basic, broad principles of comma use. Learning these ten fundamental applications of the comma will not solve all your problems with this mark, but doing so will solve the majority of them.

1. Use a comma to separate long independent clauses in a compound sentence.

Examples:

• Jack has not replied to my letter, and I don't think he ever will.
• She tried to interest him in the stock, but he insisted that he would invest his money in real estate.

2. Use commas to set off introductory words, phrases, or clauses from an independent clause which follows.

Examples:

• As a consequence, all men are created equal.
• A retiring and unusually timid man, he refused even to consider the nomination.
• When they had finished eating dinner and washing the dishes, they left for the theater.

3. Use a pair of commas to set off nonrestrictive words, phrases, or clauses inserted within a sentence.

Examples:

• It was true, however, that he did not like to come to class late.
• John, according to others to whom we spoke, was finally getting over his cold.
• On that occasion, it seems, he was driving carelessly.

4. Use commas to divide words, phrases, or clauses placed in a series.

Examples:

• She blushed, stammered, and burst into tears.
• He went to the store, to the house, and to the school.
• She is beautiful, she is smart, and she is rich.

5. Use commas between transposed names or initials, in dates, and between cities and states, etc.

Examples:

• Both Smith, Harold, and Smith, J.W., were nominated for the position.
• John Jones sailed for Europe on January 1, 1964.
• The Midway Driller is published in Taft, California.

6. Use a comma, or commas, to prevent misreading.

Examples:

• The morning after the policeman came to the door. (The morning after, the policeman came to the door.)
• In 1942 361 men from this town entered military service. (In 1942, 361 men from this town entered military service.)
• Let's eat Grandfather before we go. (Let's eat, Grandfather, before we go.)

7. Use a comma or commas between coordinate adjectives which modify their nouns equally.

Examples:

• The big, strong linebacker tackled the puny, awkward quarterback.
  BUT NOT:
  
• The hot August sun burned brightly over the Mid-Western Texas town.

8. When directly addressing others, the direct address needs to be separated from the rest of the sentence with a comma or commas.

Examples:

• Sir, will you hand me that paper.
• Let's go, Bob, before it's too late.
• You did a very good job, Robert.

9. In direct quotations, a comma or commas need to be used to separate the tag--an indication who is speaking--from the actual direct quote.

Examples:

• John said, "Please take out the garbage."
• "Please," John said, "take out the garbage."
• "Please take out the garbage," John said.

10. A word or group of words which modify the noun preceding it or them is called an appositive. Appositives need to be separated from the remainder of the sentence with a comma or commas, depending on placement.

Examples:

• George Bush, an ex-President of the United States, was elected to office.
• The dog, big and ugly, attacked the mailman.
• Utah, a state in the Mid-Western United States, is cold this time of year.
• I was born in Taft, a town in the South-Western San Joaquin Valley of California.

Back to Helpful Documents.

Back to OWL