A good indicator of a verb's argument structure is the entailments of sentences containing the verb. For example, the optional prepositional phrases in (3.44a) seem to be optional complements of the verb complain rather than adjuncts due to the entailments displayed in (3.44b). (Examples from Wechsler 1991.)
John complained (to Mary) (about the heat).
John complained.
John complained
to x about y.
In contrast, adjunctive prepositional phrases do not result in such entailment patterns, as shown in d38. These entailment patterns indicate whether or not particular semantic information is directly relevant to the meaning of the verb. Information which is not directly relevant should be treated as an adjunct rather than an argument.
John sang (to Mary) (about his homeland).
John sang.
John sang to
x.
John sang about y.
Considering the application of this test to -datives, we find the entailment patterns in d39. The data supports Jackendoff's assertion (see Section 3.2.1) that some -datives require the PP as an argument, while for others it is an adjunct. Particularly interesting is the contrast between (3.46b) and (3.46c). The notion of a recipient is more central to the notion of sending than to kicking, since send necessarily involves an (intended) transfer, while kick does not. Thus there are semantic differences in the relationship these verbs have to the to-PP which were not reflected in the syntactic tests for argument structure, where these two verbs behave similarly with respect to the attachment of the PPs.
Adam told a story.
Adam told a story
to x.
Sam sent a letter.
Sam sent a letter
to x.
Sam kicked a ball.
Sam kicked a
ball to x.
Applying the test to -datives, we have the entailment patterns in d40. The information added by the PPs thus seems to be adjunctive.
Adam baked a cake.
Adam baked a
cake for x.
Adam sang a song.
Adam sang a
song for x.
However, the semantic intuitions about the adjunctive nature of -datives become a bit confused when we consider the data in d11 (from Haegeman 1991).
Hercule bought a detective story for Jane. Hercule bought Jane a detective story. Hercule bought a detective story.
In an unmarked context, (3.48c) is taken to mean that Hercule
bought the story for himself. This suggests that the semantic
relation of buying includes the person for whom the bought
object is intended. Thus, (3.48c)
Hercule bought a detective story for x. This would seem to
argue against the treatment of the -PP as an adjunct for the verb
buy, but the semantic intuitions about -datives remain
valid in the general case.