Anonymous“a genuine passive construction”
Your
question elicits another. What is a genuine passive construction?
If, to be genuine, the passive construction must be a main clause as in The man was bitten by the dog,
then no, there is no
genuine passive construction in that sentence. There is a passive
construction in the underlying relative clause, however. I don't
know if that's genuine enough for you!
The underlying structure is
That a single man in possession of a good fortune must be in want of a wife is a truth which is universally acknowledged.
Two transformations (Extraposition and Whiz-deletion) apply to generate the final form.
Extraposition is the substitution of it for the subject that clause and movement of the that clause to the end.
Whiz-deletion is the removal of the which is that introduces the relative clause.
CJ