The document discusses syntax and sentence structure. It defines the basic units of syntax as the sentence, subject and predicate. It identifies four types of sentences: declarative, interrogative, imperative and exclamative. It also defines phrases, clauses and the four sentence structures: simple, compound, complex and compound-complex. Key terms discussed include nouns, verbs, finite verbs, coordinating conjunctions and subordinating conjunctions. Examples are provided to illustrate different sentence types, phrases and clause structures.