I have to disagree with the idea that _unfortunately_ in "Unfortunately,
he failed the test" modifies the verb and not the entire sentence. If it
were to modify the verb, it would have a different meaning from that
conveyed by the sentence, which is something like: "It is unfortunate
that he failed the test." And in addition, I disagree that "According to
Hoyle" is a 'participial.' There is no corresponding verb form that means
the same as "according to" and most references cite it as a multi-word
preposition. Finally, I do agree that the infinitive construction in
complex transitive constructions with the verb _force_ is an "objective
complement", though I call these 'predicate complements.' I give an
extended discussion of such infinitives in my book _Grammar in Many
Voices_ (1995), published by NTC Publishing Group in Lincolnwood IL.
 
Marilyn Silva
California State University, Hayward
.