(^132) Chapter 7 Prepositions and preposition phrases
The [a] examples, with a PP functioning as complement of be, are impeccable, but
the [b] ones, with an adverb in this function, are ungrammatical.
Instead of [ib] we have Lucy was enthusiastic today, with the corresponding
adjective.
Since the adverb again has no adjective counterpart we cannot correct [iib] in the
same way; for this particular example we could have It is raining again, with
again now functioning as modifier to the verb rain.
The classification of words like aboard and outside as adverbs is thus inconsistent
with the traditional definition of that category. The best way to remove this inconsis
tency is to amend the definition of prepositions so that they are no longer required to
have an NP complement. Aboard, outside and similar words will then be prepositions
both when they have NP complements and when they occur alone. This revision
simultaneously gets rid of the complication of a dual classification for these words
and removes from the adverb class words which differ radically in their syntactic
properties from genuine adverbs, thus making it a significantly more coherent class.
Notice in particular that with our more restricted class of adverbs, but not with the
larger class of traditional grammar, all functions that can be filled by adverbs accept
some of the most central type, the type formed from adjectives by adding ·ly.
This revision of the traditional analysis is not an original idea of ours. The core of
it was first put forward as early as 1924 by the great Danish grammarian Otto
Jespersen, and it is adopted in much work in linguistics since the 1970s.
One reason why traditional grammarians have not taken it up may have to do with
the etymology, or historical source, of the term 'preposition'. This suggests a word
placed in front of another word - the traditional preposition is a word placed in front
of a noun (or NP, in our analysis). It may therefore seem undesirable to apply the
term to a word which is not positioned in front of an NP. But there are three points
to be made in favour of doing so.
First, prepositions do not always precede their complements: in What are you
looking fo r? the prepositionfor does not precede its complement what (see §5 for
more discussion of this construction).
Second, no one worries that the etymology of 'adverb' suggests a word depend
ent on a verb, although the term applies also to words modifying adjectives, other
adverbs, and so on.
Third, the term 'preposition' is so deeply ingrained in the grammatical tradition
that there would inevitably be a great deal of opposition to a newly invented
replacement; it is better just to recognise that words often change their meanings,
and to accept a change in the meaning of 'preposition'. The property of being
placed before an NP will still apply in central cases, but not in all.
Further extensions of the preposition category
Once we remove the requirement that a preposition must have an NP complement,
the way is open for us to reassign to this category a number of other words that are
traditionally analysed as adverbs. There are a good number of words that behave like