Quick Guide to Commas Wayne State University School of Social Work What is a Comma? Merriam-Webster (2012) defines a comma as: “A punctuation mark, used especially as a mark of separation within the sentence” (para. 1). Commas tell a reader to pause in a sentence much like a driver yields to a blinking yellow before proceeding (“Punctuation Made Simple”, n.d.). http://lilt.ilstu.edu/golson/punctuation/comma.html Clauses Independent Clause: A group of words that contain a subject and verb and completes a thought. Example: Jess shopped for new running shoes. Clauses Dependent Clause: A group of words that contain a subject and a verb but does not express a complete thought. Example: When Jess shopped for new running shoes...(What happened when Jess shopped for new running shoes?) Often, dependent clauses contain marker words. Marker words: after, as, as if, because, before, if, since, though, unless, until, whatever, when, whenever, whether, and while (to name a few). Commas We use commas to separate independent clauses when joined by a coordinating conjunction. Coordinating conjunctions: but, and, or, so, nor, yet, and for. Example: Jess shopped for running shoes, but the store was closed “Jess shopped for shoes.” and “The store was closed.” are independent clauses joined by a comma and a coordinating conjunction. Commas We use commas following an introductory clause: Starter words for introductory clauses: although, if, since, when, while. Example: While Jess was shopping for running shoes, she misplaced her keys. Commas We use commas in the middle of sentences “to set off clauses, phrases, and words that are not essential to the meaning of the sentence.” These are often called “parenthetical elements” or “added information” Example: Last Wednesday, which was my birthday, was the pep rally. Clues: Does the sentence still make sense if we take the clause away? These can be very subjective. http://owl.english.purdue.edu/owl/resource/607/02/ Commas We use commas to separate three or more words, phrases, or clauses written in a series Jess’ new car was red, sporty, and fast. All of the above adjectives carry the same weight in describing the noun. Commas We use commas to set off phrases that express contrast. Example: Jess’ new running shoes were on sale, not regular price. We use commas to set off phrases at the end of the sentence that refer to the beginning or middle of the sentence. Example: Jess ran the marathon enthusiastically, waving at the crowds. Commas We use commas to set off quoted elements. Example: As Jess stated, “I love my new running shoes.” We use commas to set off all geographical names, items in dates (except the month and day), addresses (except the street number and name), and titles in names. Examples: Detroit, Michigan June 27, 1976, is my birthday No comma needed to separate month/year (June 2012). Comma Abuse There are many reasons for using commas, and only the most common uses are listed. Yet the biggest problem that most students have with commas is their overuse. Remember, too, that a pause in reading is not always a reliable reason to use a comma. Try not to use a comma unless you can apply a specific to do so. Comma Abuse We do not use commas to separate a subject and verb. Example: The most important quality in a person, is their sense of humor. We do not use commas between the two verbs in a compound predicate. Compound predicate: Usually tells us what the subject is doing, or what is happening to the subject. Example: Jess put on her new running shoes, and began to run. Semicolons As previously stated, we use commas after the first independent clause when you link two independent clauses with a coordinating conjunction. We use semicolons when two independent clauses are linked with no connecting words (coordinating conjunctions). Example: It rained during Jess’ marathon; she managed to finish it anyway. Semicolons We also use a semicolon when two independent clauses are joined together with a conjunctive adverb. Conjunctive adverb: however, moreover, therefore, otherwise, thus, etc. Example: It rained during Jess’ marathon; however, she managed to finish it. Semicolons Do not use a semicolon with a coordinating conjunction. Conjunctions: and, but, or, nor, for, so, and yet. Example: Jess’ shoe became loose during the marathon; but she managed to finish it. Not Correct. There is one instance in which it is appropriate to use a semicolon with a coordinating conjunction. Within a list of items where commas are used to separate items. A semicolon may be used to separate a grouping. Example: The winners are: John H. of Detroit, MI; Joan P. of Dallas, TX; and Sam C. of Orlando, FL. Further Reading New York Times http://opinionator.blogs.nytimes.com/2012/05/21/the-mostcomma-mistakes/ APA Styl Manual p. 88, section 4.03 Thank you! For further assistance with commas and semicolons, please schedule an appointment with your Writing Tutor!