Chapter 1 - Grammatical Foundations: Wordsconstruction. However, an adjective (stupid) and a verb (fishing) cannot occupy this
position. We might claim therefore that this position can only be occupied by [–V]
categories.
We see from the discussion above the predictive power of the system that we have
set up: the system predicted that there should be a fourth thematic category that has
certain properties and these fit the category of prepositions very well. We can take this
as evidence in favour of this system of features. What else does the system predict? It
is clearly predicted that if we add a third binary feature to the two we have just been
discussing, then a further four categories will be defined. This again matches perfectly
with the description of categories we started this section with, as seen in (23). With the
third feature, [±F], there should be four functional categories which match the four
thematic categories in terms of their feature settings for [±N] and [±V]. We have
already seen how determiners and modals can be analysed as functional nouns and
functional verbs, respectively. The expectation is that degree adverbs, such as so and
too, and complementisers, such as that and if, should be related to adjectives and
prepositions in the same way. As degree adverbs modify adjectives in a very similar
way to how determiners modify nouns, it is not difficult to conclude that degree
adverbs are functional adjectives. This leaves complementisers to fill the final place as
functional prepositions. There is evidence in favour of this assumption, but it rests on
notions not yet introduced, so we will have to wait until later to demonstrate it.
We can re-draw the typology given in (23) using the three features in the following way:
(32) Words
–F +F
–N,+V +N,–V +N,+V –N,–V –N,+V +N,–V +N,+V –N,–V
(verb) (noun) (adj.) (prep.) (infl) (det) (deg) (comp)
A further advantage of this system is that it places restrictions on what categories
we can suppose to exist, hence increasing its explanatory power. For example, we
would not be entitled to come up with an extra category without destroying the system
developed. One way to add extra possible categories within the system would be to
declare another binary feature. But this would not allow the addition of one extra
category, but a further eight! Moreover, these extra categories would have to be shown
to be related and opposed to the existing categories in the same way that these are
related and opposed to each other.
Another way to extend the system, which we will be making some use of, relies on
the notion of underspecification of features. All the categories discussed above are fully
specified for all the features, so each is associated with a plus or minus value for all three
features. Underspecification is a situation in which one or more features is not specified
for its value. Thus, we might propose a new category [+N, –V] which is not specified for
the [±F] feature. This category would then be a noun which is neither functional, nor
thematic. We will see that there is evidence that the [±F] feature can be left
underspecified and hence there are a further four ‘non-functional’ categories. We will
introduce these categories in the following sections. The important point for the moment
is that the system of features restricts our ability to invent new categories ‘willy-nilly’.