The Impersonal Passive
This structure is used in formal writing and news reporting to express what people generally say, think, or believe, without specifying exactly who said it.
Structure 1: It is + past participle + that clause
Verbs commonly used: say, think, believe, know, claim, report.
Active: People say that he is rich. Passive: It is said that he is rich.
Structure 2: Subject + passive verb + to-infinitive
This is a more advanced, condensed way of saying the same thing.
He is said to be rich. The company is reported to be losing money.
For Past Actions
If the reported action happened in the past, use the perfect infinitive (to have + past participle).
He is believed to have stolen the money.