PUNCTUATION2：COMMA.docVIP

Title：Comma Commas are the most frequently used punctuation mark in English. Originally used to show a pause, they are used nowadays in a variety of situations to make writing clearer. 1. The Three Most Common Comma Rules While there are many specific uses for commas, nearly eighty-five percent of the commas used in written English are used in a mere three situations. If you know the basic rule for these three cases, you can use commas in over four-fifths of the times you need to use commas. A. Put a comma before a coordinating conjunction that separates two independent clauses. B. Put a comma after introductory words, phrases, or clauses in a sentence. Commas and Introductory Words or Phrases Commas are used to set off certain items that often begin a sentence and have no grammatical connection with the rest of the sentence. These items include certain common expressions, unemphatic interjections, and direct addresses. Common Expression: But of course, we have mustard in the car. Unemphatic Interjection: Yes, we have no bananas. Direct Address: Robert, please hand the man some mustard. All three of these items are set off by commas no matter where they appear in the sentence. If they are not used at the beginning, the sentence often sounds more awkward. Correct: Please, Robert, hand the gentleman some mustard. Correct: We have mustard in our car, of course. Introductory adverbs are normally set off by a comma unless they are followed directly by the word they modify. Correct: Clearly, one and one make two. Incorrect: Clearly, mistaken was the witness. (Clearly modifies mistaken which directly follows it because of a change in the word order.) Correct: Clearly mistaken was the witness. C. Use commas to set off elements that interrupt or add information in a sentence. a. Commas with Interrupting and Parenthetical Expressions Correct: John headed this way; however, he did not see me. Correct: John headed this way; he did not see me, however. S