From C1, it follows that this selectionally introduced contextual feature is, apparently, determined by an abstract underlying order. So far, a subset of English sentences interesting on quite independent grounds is not to be considered in determining the ultimate standard that determines the accuracy of any proposed grammar. For any transformation which is sufficiently diversified in application to be of any interest, relational information does not readily tolerate a parasitic gap construction. To characterize a linguistic level L, the fundamental error of regarding functional notions as categorial is necessary to impose an interpretation on the system of base rules exclusive of the lexicon. Let us continue to suppose that a descriptively adequate grammar is rather different from a corpus of utterance tokens upon which conformity has been defined by the paired utterance test.
see also: WikiPedia -- Chomskybot