This document discusses different types of sentences. It defines a sentence as a group of words that expresses a complete thought and includes a subject and predicate. There are three main types of sentences: simple sentences, which contain a subject and predicate; compound sentences, which contain at least two independent clauses joined by a coordinating conjunction; and complex sentences, which have one independent clause and at least one dependent clause introduced by a subordinating conjunction. Examples and diagrams are provided to illustrate each sentence type. Key parts of a sentence like the subject, predicate, and phrases are also defined.