1. Use commas to separate items in a series of three or more things. An Item may refer to a noun,, verb, or adjective phrase. Usage of a comma to separate the second-to-last item is optional. Oxford comma.
Using the Oxford comma, be consistent in using or not.
Examples:
The toolbox has a hammer, screwdriver, and a wrench.
This recipe requires bacon, spinach, and tomatoes.
Some of my favorite activities are visiting the library, walking in the woods, and planting in my garden.
2. Use a comma to separate independent clauses (complete thoughts) when they are joined by the following conjunctions
For And Nor But Or Yet So
FANBOY
Examples
All of the repairs on the car have been completed, but it is still not running.
There are three coffee shops in the area, but none are open today.
3. Use a comma to separate a dependent clause (incomplete thought) from an independent clause (complete thought).
If you start with an independent clause, you do not need to put the comma.
Examples
Because all the coffee shops in the area were closed, we went to a restaurant.
Although the committee will reconsider my project in six months, my project was rejected.
4. Use a comma to separate any word or phrase from the rest of the sentence that isn’t essential to the sentence’s meaning.
Examples
The geese, who were white with a black ring around their necks, slowly swarm around the lake.
With red lights swirling and sirens blaring, a firetruck came speeding down the street.
5. Use a comma to separate a quotation from the rest of the sentence.
Examples
Frankenstein's monster, while speaking to Dr. Frankenstein said , "Beware; for I am fearless, and therefore powerful. I will watch with the wiliness of a snake, that I may sting with its venom. Man, you shall repent of the injuries you inflict."
As Gandalf tried to grasp at the stone, he began to fall as he cried, "Fly, you fools!" and was gone.
6. Use a comma to separate an introductory element from the rest of a sentence.
Examples
After finishing dinner, I went to the park
With a smile on her face, Julia opened the door.
Before the concert, the musicians rehearsed their planned songs.
As the sun set, the sky turned shakes of pink and orange.
7. Use a comma to separate the name of a city from a country or state.
Examples
Gotham City, New Jersey
Sunnydale, California
Pyrus, Genovia
8. Use a comma to separate the day of the week, the day of the month, and the year.
Examples