The Use of Commas

Commas are one of the most frequently used and misused punctuation marks in the English language. The English language has 8 key rules that you need to know about using commas:

1. One of the most common uses of commas is to separate two independent clauses that are connected by one of a special set of conjunctions. The best way to understand or identify independent clauses is to know that they are sets of words that make up a complete sentence, including a subject and a verb. Sometimes, two independent clauses like this are joined together in the same sentence and may require a comma for clarification. There is a special set of conjunctions that can be used to connect independent clauses within a sentence; the easiest way to remember them is to learn the word “FANBOYS,” which stands for “for,” “and,” “nor,” “but,” “or,” “yet,” and “so.” Thus, the following example sentence requires a comma.

  • “The first act of the play was very long, so the couple had to leave before the second act.”

2. Another common use of commas is to separate a list of three or more items within a sentence as follows:

  • “She went to the grocery store to purchase eggs, milk, bread, and soap.”

3. Commas are used to introduce a quotation and often follow words like “said,” “answered,” and “yelled.”

  • “After finishing the marathon, Sarah breathlessly exclaimed, ‘I’ve won!’”

4. When full dates and locations are used in a sentence, commas are used. A comma should be placed between the city and state and after the state in a sentence.

“He recently moved to Lexington, Kentucky, to go to college.”

Also, when a full date is in a sentence, a comma is used after the day and the year.

  • “On July 1, 1975, Sarah and Billy were married.”

5. Commas are used at the end of a sentence when there is a contrasting phrase or element. The following examples provide some clarification.

  • “She was simply lazy, not stupid.”
  • “She was one of the student who was caught, wasn’t she?”

6. Sometimes, commas are used between two adjectives that describe the same noun. This rule does not apply in all cases; it only applies when the order adjectives could be reversed and when the word the word “and” could be placed in between the adjectives.

  • “The cat had long, soft fur.”
  • “The short, bright vase was just what the interior designer wanted.”

7. Use commas to separate an optional phrase or clause from the rest of the sentence. You will know a phrase is optional if it could be removed from the sentence without changing the sentence’s meaning.

  • “July 4th, which also happens to be Independence Day, is my birthday.”

8. Finally, use a comma after an introductory phrase that comes before the main part of the sentence.

  • “When the weather gets warmer, we will start grilling outside.”
  • “For the rest of the day, we are planning to paint the house.”