This document discusses the difference between active and passive voice in sentences. It notes that active voice focuses on the subject performing the action, while passive voice focuses on the action itself or the recipient of the action. It provides examples of rewriting sentences from active to passive voice by changing the subject to the object of the active sentence and using a form of "to be" plus the past participle verb. The document also discusses when to include or omit the agent (person or thing performing the action) in passive voice sentences.