When you join two simple sentences together, you create a compound sentence. Always use a comma and one of the coordinating conjunctions to join two simple sentences into a compound sentence. The coordinating conjunctions are also known as the FANBOYS – for, and, nor, but, or, yet, so
Bob is a doctor, and his wife is a pharmacist.
Our dog got out of the yard, but a neighbor brought him back.
I have to work on Saturday night, so I can’t come to the party.
I ate a big dinner, yet I am still hungry.
Sam can pick you up, or we can meet you at the theater.
Join two simple sentences together to create a compound sentence. Always use a comma and one of the FANBOYS to join the two simple sentences.
▶Now you try it. Use a comma and one of the FANBOYS to join these two simple sentences into a compound sentence: John is doing his homework. Susan is watering the plants. That wasn’t too difficult, was it?