It be (in

Apuntes

•Introduction to Impersonal Passive Voice It is (in the correct tense) said, believed, thought, assumed, or known that clause (what people believe...). We use this form to explain what people think, say, believe, assume, or know. There are two different constructions. •Easy Construction It is known that dolphins are very intelligent. (Nowadays, people know that dolphins are very intelligent.) It has been said that the president knew about the situation. (This morning, some people said that the president knew about the situation.) •More Complex Construction Dolphins are known to be very intelligent. (present) (The same as "Nowadays, people know that dolphins are very intelligent.") The president has been said to have known about the situation. (past) (This morning, some people said that the president knew about the situation.) •Conclusion I know these structures might seem unusual, but they are very useful and common.