A compound sentence is a sentence that contains two or more independent clauses that are connected by a conjunction or punctuation such as a semicolon. An independent clause is a group of words that can stand on its own as a complete sentence because it contains a subject and verb and expresses a complete thought. Here are some examples of compound sentences in Engpsh:

"I went to the store, but I didn't buy anything."
"I'm tired because I stayed up late studying, and I have a test tomorrow."
"I'm going to the movies; do you want to come with me?"
"I pke pizza, but my friend prefers tacos."

I hope this helps! Let me know if you have any other questions.