All tenses can be changed to the passive voice. The sentences you cite from you grammar book are correct (except for a missing comma in #1 after the word 'people').
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AnonymousI wonder if the past perfect (negative or interrogative form) can be in the passive voice.Yes. All tenses can occur in the affirmative, negative, interrogative, and negative interrogative forms in the active or passive voice, if that's what you're asking.