This document summarizes the different types of clauses, including main and subordinate clauses. It discusses that subordinate clauses are less important than main clauses and can often be deleted. The types of subordinate clauses covered are relative clauses, adverbial clauses, noun clauses, and complement clauses. Finite clauses carry tense while non-finite clauses do not. Examples are provided to illustrate the different clause types and their functions within sentences.