Serial comma

In addition to helping to convey your voice and personality, commas are often used misused. There are two common errors that all college-bound students should be aware of the comma splice, and the serial comma. 

A serial comma is the one used last in a list of items, after the word and. For instance, notice the comma after apples is the serial comma ... 

The lack of a serial comma can cause confusion. In the sentence, Cindy, Ann, and Sally were hired to work in the college counselor s office, the message is straightforward. But if the serial comma is dropped, it could be understood as Cindy being told that Ann and Sally were hired. Cindy, Ann and Sally were hired to work in the college counselor s office. 

While its use has been debated for centuries, the serial comma clarifies the meaning of sentences. Therefore, you should use it consistently whenever writing a list. 

Use a comma before the coordinating conjunction in a series of words, phrases, or clauses of equal rank containing three or more items. (This comma is called the serial comma.)... 

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