Next: Summary
Up: Lexical Organization
Previous: Implementation
We have used our tool to specify a grammar for English in order to produce
the trees used in the current English XTAG grammar.
We have also used our tool
to generate a large grammar for Chinese.
In designing these
grammars, we have tried to specify the grammars to reflect the similarities and
the differences between the languages. The major features of our specification
of these two grammars28.3
are summarized in Table D.1 and D.2.
|
English |
Chinese |
examples |
passive |
bei-construction |
of LRRs |
dative-shift |
object fronting |
|
ergative |
ba-construction |
examples |
wh-question |
topicalization |
of transformation |
relativization |
relativization |
blocks |
declarative |
argument-drop |
# LRRs |
6 |
12 |
# subcat blocks |
34 |
24 |
# trans blocks |
8 |
15 |
# subcat frames |
43 |
23 |
# trees generated |
638 |
280 |
- {Major features of English and Chinese grammars
|
both grammars |
English |
Chinese |
|
causative |
long passive |
VO-inversion |
LRRs |
short passive |
ergative |
ba-const |
|
|
dative-shift |
|
|
topicalization |
|
|
trans blocks |
relativization |
gerund |
argument-drop |
|
declarative |
|
|
|
NP/S subject |
|
zero-subject |
subcat blocks |
S/NP/PP object |
PL object |
preverbal object |
|
V predicate |
prep predicate |
|
- {Comparison of the two grammars
By focusing on the specification of individual grammatical information, we
have been able to generate nearly all of the trees from the tree families
used in the current English grammar developed at Penn28.4.
Our approach, has also exposed certain gaps in the Penn grammar.
We are encouraged with the utility of our tool and the ease with which this
large-scale grammar was developed.
We are currently working on expanding the contents of
subcategorization frame to include
trees for other categories of words. For example,
a frame which has no specifier and one NP complement
and whose predicate is a preposition will correspond to
PP
P NP tree. We'll also introduce a modifier field
and semantic features, so that the head features will propagate
from modifiee to modified node, while non-head features from
the predicate as the head of the modifier will be passed to
the modified node.
Next: Summary
Up: Lexical Organization
Previous: Implementation
XTAG Project
http://www.cis.upenn.edu/~xtag