Chapter 6 - Inflectional PhrasesNote that this is a fundamentally different type of structure than the VP that we
investigated in the previous chapter. In the VP, apart from the main verb itself, light
verbs, both -assigning and aspectual types, select verbal complements and project a
verbal phrase. Hence one light verb can take a complement headed by another and a
complex VP can be built. Inflections, however, take verbal complements but project an
IP. This accounts straightforwardly for why there can only be one inflection per clause
as there can only be one IP per clause.
What is the nature of the IP and what else does it contain? Just as inflections are
always followed by the VP, they are also typically preceded by the subject in its
surface position, though as we pointed out the subject originates inside the VP (vP) at
D-structure and moves to get Case:
(3) a Maggie 1 might [vP t 1 mend the lawn mower]
b for Tony 1 to [type the letter] (would be helpful)
c Harry 1 had [vP t 1 helped the police]
A phrasal position to the left of a head could be taken to be its specifier. Clearly the
subject is a phrase and it always precedes the inflection at S-structure and hence we
might assume that the position to which the subject moves, when it leaves the VP, is
the specifier of the IP:
(4) IP
DP I'
no one 1 I vP
will t 1 dance tonight
Note that apart from complementisers, which we will discuss in the next chapter, and
adverbials, which we will discuss at the end of the present chapter, this structure
accounts for all elements of the clause. Specifically we have a subject position, an
inflection and a VP predicate: the three obligatory parts of the clause. It seems
reasonable to claim therefore that the IP IS the clause. This point of view addresses an
issue raised in chapter 3 concerning the exocentric nature of the clause. There we
discussed reasons for not considering the subject or the VP as the heads of the sentence
as they do not seem to have the right properties of a head. Traditionally therefore it has
been assumed that clauses are headless.
However, the traditional assumption is challenged by the analysis in (4), where it is
claimed that clauses most definitely do have heads. There is much evidence to support
this. Firstly consider the relationship between the inflection and the clause. The
inflections come in two basic types: finite and non-finite. The finite inflections consist
of the modal auxiliaries and tense morphemes. The infinitival marker to is non-finite,
but we also get clauses, traditionally called participles, in which the inflection on the
highest verbal element is either ing or en (or one of its irregular versions):
(5) a we are anxious [for Sam to succeed]
b the crowd watched [the fire brigade rescuing the cat]
c I saw [the cat rescued by the fire brigade]