QUES: acceptable
ANS: his belief that Mary kissed Bill is mistaken.

QUES: unacceptable
ANS: Which packages is it possible that Sam didn't pick up which are to be mailed tomorrow until it had stopped raining?

QUES: unacceptable
ANS: I know which book Mag read, and which book Bob asked why you hadn't.

QUES: acceptable
ANS:
Willy is taller than Bill by as much a Peter believes that Billy is taller than Dan.