Prepositional object vs. obligatory adverbial complement

Question

I am trying to define the exact difference between prepositional object and obligatory adverbial complement in order to study word ordering. As both complement the meaning of the verb and the adverbial complement may have a preposition, I am somewhat confused.

Prepositional object:

• Dieses Jahr besteht das Examen aus drei Teilen.
• Hast du den Brief an mich addressiert?

Obligatory adverbial complement:

• Er hat schlug mir das Glas aus der Hand.
• Sie wohnen in München / schön / mit ihrem Vater.

I see that the adverbial complement always refer to time, manner, place, companionship and that the prep. object does not, but I was looking for a more precise distinction.

Answer 1

Probably the best way to tell apart a prepositional object from an adverbial is to look at how you ask for it.

If you use a interrogative containing the preposition, you're dealing with a prepositional object.

If the interrogative asks for time, place etc. in a general way (Wo? Wann? Wie?), it's an adverbial.

In your examples (1) and (2) one would ask:

Woraus besteht das Examen?

An wen hast du den Brief addressiert?

In example (4) one would ask:

Wo/Wie wohnen Sie?

(3) is tricky. If one wants to ask for the hand, one ends up with the stylistically unsatisfactory "Woraus schlug er Ihnen das Glas?" So I would argue that in this context, aus der Hand is a prepositional object, not an adverbial.