The document discusses the passive voice and how it differs from the active voice. It provides examples of sentences written in both the active and passive voice. The general rule for passive voice is that the subject becomes the object, the object becomes the subject, and the subject of the active sentence is added at the end of the passive sentence, introduced by "by". Various tenses, like present simple, past, future, and modal verbs are discussed in terms of how they are conjugated in the passive voice.