The document defines and provides examples of basic sentence elements including the subject, predicate, object, and different types of clauses. It explains that a subject is the doer of the action or topic of the sentence. A predicate states something about the subject. An object receives the action of the verb. Sentences can be simple, compound, complex, or compound-complex depending on the number and types of clauses. Fragments and run-on sentences are errors that occur when clauses are not properly connected.