This document discusses subordination and complex sentences. It defines clauses, independent clauses, and dependent clauses. Dependent clauses require an independent clause to give them meaning. The document provides examples of combining simple sentences into complex sentences by changing one clause into a dependent clause and placing it at the beginning or end of the sentence. It discusses using subordinating conjunctions to subordinate an independent clause. Complex sentences contain one independent clause and one or more dependent clauses. Punctuation rules for complex sentences are also covered. The document concludes with exercises for students to practice creating complex sentences.