There are different types of sentences that can use passive voice and infinitives. The passive voice rearranges the active sentence to make the subject receive the action. For example, "You are loved by me" instead of "I love you". Infinitives are the base form of the verb and can be used after modal verbs like "must" or "should" or to express purpose like "to be loved". Both passive voice and infinitives add flexibility and variety to sentences.