If you say that something is ~ to be true, you mean that people say it is true, but you do not know if it is definitely true. (FORMAL)
The monster, which is ~ to live in the deep dark water of a Scottish loch...
V-PASSIVE: be V-ed to-inf vagueness
~ly
He ~ly earns two million pounds a year...
ADV: ADV with cl/group, ADV before v