Rules for Commas

The comma is a valuable, useful punctuation device because it separates the structural elements of sentences into manageable segments. The rules provided here are those found in traditional handbooks; however, in certain rhetorical contexts and for specific purposes, these rules may be broken.

1. Use a comma to separate 2 independent clauses joined by

*when so means as a result

Example: 

     Jenny wants to help feed the poor, so she is planning on going to Africa this summer.

     The doctor would like to see you, but he has been at the hospital all day.

When the 2 independent clauses are very short, some people don't use commas.  However, if you use a comma, it is still okay.

     Joseph likes cheese cake, but Carol likes chocolate cake.

     Joseph likes cheese cake but Carol likes chocolate cake.

2. If there is a list of three or more items, use a comma.

     Mom bought grapes and bananas.  (no commas)

     Mom bought grapes, bananas, and strawberries.

3. If there are two or more adjectives in a row.

     Tim is a handsome, smart man.

4.  When a dependent clause, unnecessary word, or unnecessary phrase AND an independent clause are put together, there is usually a comma.  

     Unless I see you, I won't go.

     Though George is president of the company, he can still be fired.

      When Mei was in Taiwan, she often wrote to me.

     I won't go unless I see you.

5.  When an adjective clause is unnecessary, use commas.

     The president of the company, who is a Harvard graduate, plans on retiring at the end of the month.

6.  Use commas before a direct quote.

     Mark said, “I loved visiting China and Korea.”

7.  A name or title that is used to address or call a person to attention.

     When, Sir, you come back to this hotel, I cannot guarantee you a room. 

NOTE: When the name is with an important term of identification, don't use a comma.

     Alexander the Great

8.  A comma usually follows a transition word.  

     Robert studied for a whole week.  Therefore, he got an A+.

     Jake worked 12 hours a day.  Consequently, he earned enough money to travel the whole summer.

Comma Abuse:

1-Don't use a comma to separate the subject from the verb.

2-Don't put a comma between the two verbs or verb phrases in a compound predicate.

3-Don't put a comma between the two nouns, noun phrases, or noun clauses in a compound subject or compound object.

4-Don't put a comma after the main clause when a dependent (subordinate) clause follows it (except for cases of extreme contrast).

- The End -