Structural prepositions

STRUCTURAL PREPOSITIONS
Orientation
The phrase structure grammars utilized by TGG in its various forms use what amounts to a single joining operation, namely, concatenation. In the case of conjunction, however, transformationalists have found it necessary to introduce a conjunction marker between nodes to indicate the existence of a special relationship. Might such notation be, in effect, a first step towards the introduction of junction operations generally? Time will tell. The various relational markers for conjunction (and, or, but, etc.) are positive evidence that this is not a misguided move. But what additional evidence is there to justify the many junction operations used in Junction Grammar (JG)?
It is not the purpose of this brief exposition to restate what has previously been written about the semantic contrasts between adjunction, conjunction, and subjunction. Rather, we will direct our attention to specific phenomena which have more recently come to light that tend to support the use of an extended inventory of specialized junction operations, even more extensive than those formerly postulated.
Prosodic Relational Markers
First, positive evidence that the specializations of subjunction recently introduced into junction notation are in fact valid is available in the form of voice inflections which cue them to the listener. Specifically, the contrast between restriction and non-restriction (‘.*’ and ‘.*.’ respectively) is coded as the presence or the lack of a pause in the articulation stream when the modifier follows its antecedent.
1) John, whom we know …(.*.)
2) The John we know …(.*)
Further, the contrast between right and left subjunction is realized as emphasis on the more specific operand of the subjunction. Consider, for example, the inflection occurring on interrogative pronouns, or other forms joined to such modifiers asonly (outside the article), even,also, etc. From the perspective of junction theory, a system of representation that does not motivate prosodic relational markers is hurting in the same way that a grammar does which fails to provide for conjunctive markers in a principled way.