396. Use a Comma in a Compound Sentence

A compound sentence is two simple sentences joined together. A simple sentence looks like this:
Bob rode his bike. This sentence is a simple sentence because it is about one person doing one thing.

Here is another simple sentence: Mary rode her scooter.

If we put these two simple sentences together, we get a compound sentence: Bob rode his bike, and Mary rode her scooter.

We joined the two simple sentences into a compound sentence by putting a comma after the first simple sentence and using the conjunction and.

We can also make a compound sentence with the conjunction but:
Bob rode his bike, but Mary rode her scooter.

There are actually seven conjunctions in English, and we use all of them to make compound sentences.
for – I am sad, for my plant has died.
and – It is Monday, and I have to go to school.
nor – I am not happy, nor am I busy.
but – I am not busy, but I don’t want to read a book.
or – Do you want to eat dinner, or should we practice first?
yet – I turned up the heat, yet it is still cold in here.
so – Company is coming, so we need to clean the house.

We call these conjunctions the FANBOYS because each letter in this word is the beginning letter of a conjunction:
For
And
Nor
But
Or
Yet
So
Do you see how the first letter of each of these words forms the word FANBOYS ?
Always use a comma before one of the fanboys.

When joining two simple sentences into a compound sentence, always put a comma after the first simple sentence. Put one of the FANBOYS after the comma. Comma, FANBOYS.

▶It’s your turn. Put a comma into this compound sentence: The sun is shining but the wind is cool. Did you put a comma after the first simple sentence, before the FANBOYS conjunction? Good for you!