The verbs think, believe, say, suppose, report, know, expect, consider, understand, etc are used in passive sentences both in personal and impersonal constructions
Impersonal Passive → We form it as follows: It + passive + that-clause (se cree, se dice, se comenta, se rumorea…)
👉 People believe that men are better at maths than women
👉 It is believed that men are better at maths than women (Se cree los hombres…)
👉 People say that Maria speaks three languages
👉 It is said that Maria speaks three languages (Se dice que María habla…)
Personal Passive → We form it as follows:
If both verbs are in the same tense: Subject + passive + to infinitive
Examples
👉 People believe that he works too much
👉 He is believed to work too much → Personal Passive
👉 They think Tom is a good politician
👉 He is thought to be a good politician → Personal Passive
If the first verb is in Present and the second in Past: Subject + passive + to have + participle
👉 People believe that he worked too much → Active Voice
👉 He is believed to have worked too much → Personal Passive
👉 They think Tom was a good politician → Active Voice
👉 He is thought to have been a good politician → Personal Passive