The document discusses the active and passive voice in English grammar. It explains that in the active voice, the subject performs the action, while in the passive voice, the subject receives the action. It provides examples of sentences in the active and passive voice and discusses how to change between the two voices. The document also covers forming sentences in the passive voice for different tenses, including the present, past, and future. It notes some exceptions and concludes with exercises changing sentences between the active and passive voice.