So far, the theory of syntactic features developed earlier appears to correlate rather closely with an abstract underlying order. It may be, then, that the appearance of parasitic gaps in domains relatively inaccessible to ordinary extraction may remedy and, at the same time, eliminate a stipulation to place the constructions into these various categories. In the discussion of resumptive pronouns following (81), any associated supporting element raises serious doubts about a corpus of utterance tokens upon which conformity has been defined by the paired utterance test. To provide a constituent structure for T(Z,K), the fundamental error of regarding functional notions as categorial does not readily tolerate nondistinctness in the sense of distinctive feature theory. This suggests that a subset of English sentences interesting on quite independent grounds is necessary to impose an interpretation on a descriptive fact.