This chapter provides an overview of the key concepts in Object-oriented English Grammar. It defines a simple sentence as having a subject and predicate. It outlines the main word classes in English - nouns, pronouns, verbs, adjectives, adverbs, prepositions, articles, and conjunctions. It describes the five basic simple sentence patterns and the two types of sentences: declarative and interrogative. The chapter lays the groundwork for the analysis of English grammar using an object-oriented approach.