This document discusses infinitives in English grammar. An infinitive is a form of a verb that generally appears with "to" and can function as a noun, adjective, or adverb. Examples of infinitives include "to walk", "to talk", "to listen". The document provides examples of infinitives functioning as nouns, adjectives, and adverbs. It also discusses verbs that are followed by infinitives or gerunds (verb+ing form) and provides exercises for students to practice identifying infinitives and completing sentences with the correct verb form.