To make a compound sentence a writer uses a ___ to connect two independent clauses

Coordinating conjunctions are used in compound sentences. Remember them as 'A. B. Fonsy'-and, but, for (meaning because), or, nor, so, yet. Use a comma before a coordinating conjunction when you are writing a compound sentence. Each coordinating conjunction is used to indicate a specific type of relationship.

It could be a word, such as - for, nor, and, but, or, yet and so. But there's also the semicolon.