On the Use of Commas

On the Use of Commas 1. Put a comma before and, but, for, or, nor, yet, or so when they connect two independent clauses. ¾ I may try to get a new job, or I may stick with this one. Each of the phrases, “I may try to get a new job” and “I may stick with this one,” are independent clauses; they can be written as sentences: I may try to get a new job. I may stick with this one. Be sure that such words DO connect two independent clauses. The following sentence is merely one independent clause with one subject and two verbs. Therefore, no comma should be used. ¾ She wanted to go to college but didn’t have enough money. Notice that the phrase, “She wanted to go to college” is an independent clause and can be written as a complete sentence: She wanted to go to college. BUT the phrase, “didn’t have enough money” is a dependent clause; it cannot be written as a complete sentence because it has no subject. It is dependent upon the other clause for its subject, “She.” 2. Put a comma between items in a series. ¾ He ordered pie, cake, and ice cream. It’s permissible to omit the comma before the “and” connecting the last two members of a series, but more often a comma is used. ¾ He wore a baggy old red sweater. The bright blue morning sky lifted her. Some words “go together” and don’t need a comma between them even though they do make up a series. 3. Put a comma after an introductory expression or after a thought that doesn’t flow smoothly into the sentence. It may be a word, a group of words, or a dependent clause. ¾ Yes, I’ll go. Well, that was the end of that. It’s cold this morning, isn’t it? When a dependent clause comes at the beginning of a sentence, put a comma after it. Dependent clauses do not need commas when they come at the end of a sentence. For example, compare the following: ¾ Before he arrives, we should all hide. We should all hide before he arrives. Look for a dependent clause when the sentence contains: After Although As As if Because Even if Even Though Ever since How If Since So that Than That Though Until What Whatever When Whenever Where Whereas Wherever Whether Which Whichever While Whom Whose Why ¾ Although he ate dinner, he was still hungry. Wherever they went, they were accepted as friends. Even though these above listed words are often used in dependent clauses, they can often appear in sentences without dependent clauses. For example: ¾ Wherever did you get that hat? 4. Put commas around the name of a person spoken to. ¾ I think, Melissa, that we’re late. Chris, how about a game of chess? Are you ready, Amy? 5. Put commas around an expression that interrupts the flow of the sentence. (Such as however, moreover, finally, therefore, of course, by the way, on the other hand, I am sure, I think). ¾ He did go to class. He did, however, go to class. He arrived home. Finally, he arrived home. It was her paper. It was his paper, I think. 6. Put commas around nonessential material. Nonessential material consists of words that are not necessary for the sentence to make sense. ¾ Mariam Tilden will speak tonight. Mariam Tilden, who heads the hospital volunteers, will speak tonight. The new machine is much faster. The new machine, which was ordered by the supervisor, is much faster.