This document discusses sentence structure and the different types of sentences. It defines clauses, independent clauses, and dependent clauses. Simple sentences contain one independent clause, compound sentences contain two or more independent clauses, and complex sentences contain one independent clause and one or more dependent clauses. The document also describes the different types of dependent clauses - adjective clauses, adverb clauses, and noun clauses. Finally, it defines compound-complex sentences as containing two or more independent clauses and one or more dependent clauses.