Structural prepositions

Structural Prepositions
It is obvious that junction relations in basic data are in some cases recoded as nodes during the process of extracting information from the information net and preparing it for use in conversation. For example, consider the prepositions ‘of’ and ‘by’ in such expressions as ‘the teaching of English by the professor.’ The existence of such prepositions is positive evidence for postulating at least two kinds of adjunction, rather than a single kind. Moreover, the fact that relations may in fact be recoded as nodes suggests a technique for detecting junction contrasts not yet recognized in the notation of JG.
Specializing Adjunction
For example, consider the agentive and obgentive readings of the structural preposition of or the corresponding adjective suffix ’s. The ambiguity of these forms (the two distinct readings) clearly demonstrates that the relation between subject and predicate is not identical to that between verb and object:
1) The reading of John was sub par. (‘John reads” - agentive)
2) The reading of opposition literature was prohibited. (‘… read literature’ - obgentive) 
One is therefore justified in postulating distinct adjunction operations for the environments in question. In this case, since the adjunctive generalization previously made for these relations seems basically sound (the J-rule schemata thereby obtained have been explanatorily powerful), one would introduce specialized adjunctions for the relations in question.
Similarly,‘John seeks a house’ and ‘John builds a house’ correspond to ‘John’s seeking/search for (*of) a house’ and ‘John’s building of (for*) a house,’ where the node counterparts of the respective adjunctions again contrast. Notice also that ‘by’ does not fit with equal ease in both environments: ‘The building of a house by John’ versus ‘*the seeking for a house by John.’ While this may be simply a preference for ‘of’ in the presence of ‘by’ (notice ‘the seeking of John for a house’), intuition identifies a different role for John as an agent in each case (a creator for the predicate with ‘build’, but not for the predicate with ‘seek’). We note also in this regard that the nominal form of ‘build’ (‘building’) can refer to the result of John’s act, while the corresponding form of ‘seek’ (‘seeking’) cannot. Thus, in accordance with our hypothesis, if adjunctive contrasts are presumed to exist for ‘build’ and ‘seek’, the lexicalizations of their respective nominals are governed in terms of that same contrast.
The verb ‘love’ affords yet another example of adjunctive contrast between verb and object: ‘John loves Mary/ John loves money’ versus ‘John’s love for Mary/ John’s love of money.’ A study of verbs in general in the context of compatible structural prepositions may prove useful in refining the inventory of adjunctive relations used by the languages of the world.
It has also been proposed that an adjunctive specialization is responsible for the ambiguity of sentences such as (3), where one reading is that what happened was accidental and the other is that what happened was done on purpose:
(3) He bumped an old lady.
While this is a plausible proposal, difficulties arise for it in the case of conjoined PV’s. If the adjunctive operations were responsible for the ambiguity in question, one would expect one reading or the other to hold for an entire predicate. In the case of conjoined predicates, however, each conjunct is independent of the others in this respect. Thus, in a sentence such as (4), the first predicate is perceived to have occurred accidentally, but not the second:
(4) Jim hit his thumb with the hammer and then proceeded to curse.
To treat the contrast in question in terms of an adjunctive specialization would require that a different adjunctive relation be given for each PV conjunct. This, of, course, would be a radical departure from the standard formalism of JG.
Others have proposed that the contrast is in the subject, i.e. that a feature specifies the subject noun as being either an agent or a non-agent with respect to the predicate. This solution, however, runs into the same difficulty – the subject will have to be specified differently for each conjunct of the predicate.
Another solution is suggested by the fact that the ambiguity of (3) can be removed by attaching a modifier to the predicate (He bumped an old lady on purpose/accidentally). Similarly, for (4) each predicate conjunct can be modified differently (Jim accidentally hit his thumb and proceeded to swear on purpose.) This suggests that the contrast in question resides in predicates themselves rather than in subjects or in the relation between subjects and predicates.
Case
Insofar as a comparison with other methods of linguistic analysis and description is concerned, we have here entered into the domain of what is generally referred to as case. We defer further comment, however, for another day. For the moment, let us concentrate on the theoretical implications of relational markers and structural prepositions.