Writing styles change over the years. In Victorian times, reading was the primary form of entertainment and writers were paid by the word. Today we are in a hurry. So we follow what is called newspaper style. Books are shorter and sentences are simpler. Still, there are times when writing cries out for proper punctuation, and that includes commas. The good news is that there are only five rules you have to learn and you probably already know most of them.
Five Basic Comma Rules
1. After an introductory subordinating element in a sentence.
Examples: Yes, I'll have more cake. (single word)
After dinner, we'll go to a movie. (phrase)
Since I hate horror films, I'll stay home. (clause)
2. A pair of commas bracketing unnecessary elements in a sentence (something that could be left out without a change of basic meaning or grammatical construction).
Example: John's car, dirty from a long trip, needs a bath.
(Basic sentence is that John's car needs a bath)
3. Between words in series, the comma substituting for "and."
Examples: I went shopping for bread, milk, ice cream and eggs. (Note:
Comma between ice and cream would change meaning)
I love my new red straw hat. (No commas because
none would pass the “and“ test)
4. To separate direct quotes from the rest of the sentence.
Example: Mary said, “I hate cold weather,” and put on her coat.
5. For dates, time and titles.
Examples: On July 4, 1776, our country was born.
Jason Smith, M.D., performed the surgery.
I live at 27 Maple Ave., Chicago IL.
If you remember these five rules, your comma mistakes will be less than 2%, and anyone will forgive a small margin or error. Just remember: When in doubt, leave it out.