Notes on computational linguistics.pdf - UCLA Department of ...

Stabler - Lx 185/209 2003
(9) Let’s extend the example a little further. First, Burzio (1986) observed that, at least to a good first
approximation, a verb assigns case iff it takes an external argument. In the previous grammar, these
two consequences of using a transitive verb are achieved by two separate categories: acc and pred.
We can have both together, more in line with Burzio’s suggestion, if we allow a projection with two
specifiers. We will call this projection agrO, and we can accordingly rename i to agr0. To distinguish
transitive and intransitive verbs, we use the categories vt and v, respectively. So then our previous
grammar becomes:
ɛ::=agrS +wh c
ɛ::=agrS c
-s::=agrO +v +k3s agrS ɛ::=agrO +v +k agrS % infl
-ed::=agrO +v +k3s agrS -ed::=agrO +v +k agrS % infl
ɛ::=vt +k =d agrO ɛ::=vt +k3s =d agrO % Burzio’s generalization
ɛ::=v agrO ɛ::=v agrO % for intransitives
make::=d vt -v
eat::=d vt -v eat::=d v -v
With this grammar, we get trees like this (showing the conventional depiction):
dP3
maria
cP
c agrSP
vtP2
vt
make
t1
agrSP
agrS
-s
agrS’
t3
dP1
tortillas
agrOP
agrOP
agrO’
agrO t2
(10) Consider now how we could add auxiliary verbs. One idea is to let the verb have select a -en-verb
phrase (or perhaps a full CP, as Mahajan (2000) proposes). But then we need to get the -en phrase (or
CP) out of the VP before the VP raises to agrS. It is doubtful that the -en phrase raises to a case position,
but it is a position above the VP. For the moment, let’s assume it moves to a specifier of agrO, adding
the following lexical items to the previous grammar:
=v +aux agrO =en v -v have =agrO +v en -aux ’-en’
=prog v -v be =agrO +v prog -aux ’-ing’
=infin v -v will =agrO +v infin -aux ’-inf’
This gives us trees like the following (these lexical items are in g32.pl and can be used by the the parser
which we present in §9.2 on page 183 below):
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