 In the sentence, Mary likes this very young student of physics with blond hair, we have a relatively complex noun phrase. To understand its internal structure, let's perform the categorical analysis first. Clearly, this is a determiner. Very young is an adjectival phrase represented as a triangle. Student, the head noun, and then we have two prepositional phrases of physics and with blond hair. Again, both shown as triangles. Let's now connect them. Clearly, the adjectival phrase and the head noun form a constituent. Why? Well, we can replace them by the pro-form one, as in this one. So together with the determiner, we get this structure where the internal noun phrase is represented as n-bar, written with an apostrophe. But where shall we put the two prepositional phrases? Well, in order to integrate them into the noun phrase, we have to expand the n-bar node twice more and make the mothers of the two prepositional phrases. So this is the structure of the noun phrase. A determiner as the specifier, the noun as the head, and an internal n-bar node which can theoretically, infinitely be expanded.