The structure of IPIn the previous chapter, we analysed the morphemes in (5b) and (c) as light verbs
heading a vP and so the status of the embedded ‘clauses’ in these examples is unclear
at the moment: they may be clauses (i.e. IPs) or they may be simple vPs. We will not
attempt to deal with this issue here, returning to it in a later chapter. But there are some
similarities between these clauses and the infinitival clause in (5a) which are useful to
consider. Traditionally, those clauses containing a finite inflection are called finite
clauses and those containing a non-finite inflection are non-finite clauses. Thus the
relationship between the inflection and the clauses has been long acknowledged. I
suspect that the relative semantic unimportance of inflections and the lack of
recognition of their syntactic importance have contributed to the fact that traditional
grammars have failed to recognise them as heads.
It is important to realise that there are differences between clauses headed by finite
inflections and those headed by non-finite inflections to see that inflections really do
have a contribution to make to the clause. To start, clauses headed by a finite inflection
can be main clauses and do not have to be embedded, though they may be:
(6) a Will won’t stop the car
b I suppose [Will won’t stop the car]
In contrast, clauses headed by non-finite inflections are always embedded:
(7) a Tim to stop the car – I want [Tim to stop the car]
b Tim stopping the car – I watched [Tim stopping the car]
c *the car stolen – I saw [the car stolen]
In embedded contexts, we see another difference between finite and non-finite
clauses in that a finite clause can act as the complement of the complementiser that,
while only infinitival clauses can act as the complement of the complementiser for:
(8) a ... that [Karen could cook the dinner]
b ... that [Karen cooked the dinner]
c ... that [Karen to cook the dinner]
d ... that [Karen cooking the dinner]
e *... that [the dinner eaten]
(9) a ... for [Tracy to teach English]
b ... for [Tracy teaching English]
c ... for [English taught]
d ... for [Tracy can teach English]
e ... for [Tracy taught English]
These data not only suggest that there is a difference between finite and non-finite
clauses, but also that the infinitive and the participles have a different status, perhaps
indicating that while the infinitive has an IP status, the participles are really vPs. The
main point is, however, that different clauses distribute differently and this correlates
with which inflectional element they contain. All this adds up to the conclusion that
the inflection does behave like a head in that it projects its properties to the whole
construction and as we saw in chapter 2 it is heads that do this.