Common Rules for Using Commas

To make your writing more professional, it is important to use correct punctuation. A common mistake of many writers is the improper use of the comma. The comma is needed to separate the structure of sentences into more readable segments, offering a clearer understanding of the topic.

You should use a comma to separate independent clauses when they are joined by any of the following coordination conjunctions: and, but or, nor, so, and yet. Example: I am going home, but, I intend to come back later.

Use a comma when you want to put something it in a sentence that interrupts the flow. This could be anything from a name to a description. Examples: I want you to meet my sister, Diane, she is visiting from Colorado. The child, tired from play, fell asleep on the sofa.

Use a comma to separate parts of a series. Example: They were selling apples, peaches, melons and other fresh fruit at the farmer’s market.

Use a comma between two independent clauses together with any of the following conjunctive adverbs: however, moreover, therefore, consequently, otherwise, nevertheless, or thus. Example: It rained most of the day, therefore, we decided to go shopping.

Common starter words for introductory clauses that should be followed by a comma include: after, although, as, because, if, since, when, and while. Examples: While I was having dinner, someone came to the door. Since it was snowing, we decided to go sledding.

The comma, also, separates interjections. Example: Hey, get out of my flower garden!

Use a comma if you have a phrase before the subject allowing the reader to realize the subject is about to appear. Example: When you pass the pink barn, the antique store is just one more mile ahead. Taking a break from play, Sara rested on the picnic table.

Use a comma to off set geographical names and titles in names. Example: John Doe, Professor of Science.

When writing addresses, a comma should appear between the city and the state. Example: Martinsville, Florida.

Place a comma for items in dates (except the month and day). Example: The event will begin at 8:00 AM on Tuesday, May 21, 1992.

Use two commas to set off the year when it follows the month and day. Example: On June 1, 1992, I hope to retire and begin traveling with friends.

Do not use a comma when only the month and year are given: Example: The photo appeared in the June 1992 issue of Consumer Reports.

More information on the use of commas and other punctuation can be found online or in the Gregg Reference manual.