NOT A TEACHER
(1) I understand that there are two theories:
I = subject.
know = verb.
him = direct object.
to be honest. = objective complement (describes "him").
I = subject
know = verb
him to be honest = infinitive phrase as object of "know." ("Him" is the subject of the
infinitive "to be." In other words: I know that he is honest.)
(2) Personally, I prefer the second theory.