Theory:

Another form of the passive is called the Impersonal structure, which begins with IT:

They say he is rich. - active

He is said TO BE rich. - passive

It is said that he is rich.  impersonal

or

They say he was rich. - active

He is said TO HAVE BEEN rich. - passive

It is said that he was rich.  impersonal

Notice in the present, IS becomes TO BE, and in the past, WAS becomes TO HAVE BEEN.

These structures are commonly used with verbs like

believe

consider

think

know

expect

suppose

They BELIEVE she IS lonely.

She is BELIEVED TO BE lonely.

They CONSIDER her to be lonely.

She is CONSIDERED TO BE lonely.

They THINK she IS lonely.

She is THOUGHT TO BE lonely.

They KNOW she IS lonely.

She is KNOWN TO BE lonely.

They EXPECT she will fail.

She is EXPECTED TO fail.

They suppose it will rain.

It is supposed to rain.