82 Copyright Goodheart-Willcox Co., Inc. E Q ssential uestion What can you learn about the English language by studying sentences? Section 4.1 Sentences Objectives After completing this section, you will be able to: • Describe how sentences are structured. • Summarize types of sentence structure. Key Terms grammar sentence subject predicate direct object indirect object phrase clause independent clause dependent clause subordinating clause restrictive clause nonrestrictive clause Sentence Parts Words in the English language are classified as one of eight different parts of speech: noun, pronoun, verb, adjective, adverb, conjunction, preposition, and interjection. Grammar is the study of how words and their components come together to form sentences. It is a set of rules for using language properly. The rules of English grammar relate to how the parts of speech are used to form the sentences with which people communicate. The brief definitions of the parts of speech in Figure 4-1 will help you understand the following discussion of sentence parts. You will learn more about each part of speech later in this chapter. A sentence is a group of words that expresses a complete thought. Consider the two examples that follow. Are these sentences? Under the desk. The book is under the desk. The first example does not give a complete thought. More information is needed to understand how under the desk relates to an action, person, or thing. The second example is a sentence because it provides enough information for a complete thought.