This document discusses active and passive voice in grammar. It defines active voice as when the subject performs the action and passive voice as when the subject is affected by the action. It provides examples of sentences in active voice and their passive counterparts. It also discusses how to recognize the passive voice based on certain keywords like "be", "was", etc. and compares the differences between active and passive voice in terms of the subject, verb usage, and types of verbs that can be used.