) above, we see that the PP of Linguistics is a Complement (modifies N), whereas the PP at Reading is an Adjunct (modifies N-bar). By using the principle of structural symmetry, we see that in (2) Linguistics is a Complement because it is the sister of the N student, whereas Reading would be an Attribute because it is the sister (and daughter) of N’. It should be noted that Attributes could be either NPs or APs, in which case they are called Adjectival premodifiers (Radford, p. 216). For example, the bracketed expression in the following expression is an AP: a [very boring] film is an Adjectival premodifier.In the analysis of NPs I have shown the need for a third intermediate grammatical category, which goes to show that it is descriptively more adequate than a theory that does not recognise a small nominal unit. We adopted bar notation to capture formally the relationship of three grammatical categories, namely N’’ for the full phrase, N’ for the intermediate phrase, and N for the word level or the head of the phrase (Class notes). In order to prove that the X-Bar theory makes a contribution to explanatory adequacy, we would need to show that it is possible to apply the same phrasal analysis to the other major grammatical categories, i.e. VP, AP, PP, and ADVP and then to other languages.Before extending the phrasal analysis of the NP to the VP, let us begin by recognising the need for a third intermediate category for VPs, in the example eating a chocolate. This is shown by the fact that (1) only this unit can be preposed: a)He might have been eating a chocolate.b)Eating a chocolate he might have been.c)*Been eating a chocolate he might have.d)*Have been eating a chocolate he might.And (2) some main verbs can only be combined with a verbal unit that consists of the verb and what follows it. As in I saw Mary close the curtains, but not *I saw Mary be closing the curtains (Class notes).Verbs are similar to NPs as...
