Recent work in artificial intelligence has developed a number of
techniques which are particularly appropriate for constructing a
model of the process of understanding English sentences. These
methods are used here in the definition of a framework for linguistic
description, called "computational grammar". This framework is
employed to explore the - details of the operations involved in
transforming an representation English sentence into a general semantic
Computational grammar includes both "syntactic" and
"semantic" constructs, in order to clarify the interactions between
all the various kinds of information, and treats the
sentence-analysis process as having a semantic goal which may require
syntactic means to achieve it. The sentence-analyser is based on the
concept of an "augmented transition network grammar", modified to
minimise unwanted top-down processing and unnecessary era bedding. The
analyser does not build a purely syntactic ,structure for a sentence,
but the semantic rules operate hierarchically in a way which reflects
the traditional tree structure. The processing operations are
simplified by using temporary storage to postpone premature decisions
or to conflate different options. The computational grammar
framework has been applied to a few areas of English, including
relative clauses, referring expressions, verb phrases and tense. A
computer program ( "MCHINE") has been written which implements the
constructs of computational grammar and some of the linguistic
descriptions of English. A number of sentences have been
successfully processed by the program, which can carry on a simple.
dialogue as well as building semantic representations for isolated
sentences