Mistakes in comma usage rank among the most common among writers. While there are many rules regarding comma usage, the following five rules cover the most frequent issues that students face.
 
 A: Use a comma to separate two sentences joined by for, and, nor,
but, or, yet, and so.  (To remember this easily, memorize the mnemonic device, “fanboys.”)
 
                     Example: I wanted to come to the party, but I had to work late.
 
 B: Use a comma to separate items in a list. Note that while you may occasionally see the final comma in a list omitted (especially in journalism), it is still considered correct to include it.
 
                    Example: Scott went to the store to pick up milk, eggs, bananas, and coffee.
 
C: In a complex sentence, use a comma to separate a dependent clause at the beginning of a sentence from the independent clause at the end.
 
                    Example: Because it was raining outside, we decided to play board games indoors.
 
D: Use commas to separate interrupting words and phrases that are not part of the main narrative of a sentence.
 
                   Example: My wife, who is an elementary school teacher, has an extensive library of
                                    books for children.
 
E.: Use a comma to separate dialogue from commentary.
 
                  Example: Jack Kerouac once wrote, “I realized it’s impossible to fall off mountains.”
 
 
 
 
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