Can “to” ever be a Prep or a Particle before “be”? If so can anyone think of an example?
"Can where he went to be revealed?"
Q (where he went to can be revealed)
Q (someone can reveal Q (he went to where))
Schematically, we start with
... can reveal ... [PP to where]
which is converted to the passive,
... [PP to where] ... can be revealed
the "where" moves out of the way between "to" and "be" because the question word has to be at the beginning of the embedded question,
... [PP to] can be revealed
and finally "can" moves out of the way because it has to be inverted with the subject of the upstairs Q,
... [PP to] be ...