SAGE: a sentence parsing and generation system

s: SAG~ (Sentence Analysis and GEneration system) is an operational parsing and generating system. It is used as a Natural Language Frontend for Esprit project Eeteam-316, whose purpose is to advise a novice user through a cooperative dialogue. The aim of our system is to validate the use of a Lexice)n-Grammar (drawn from the LADL studies) ior sentence-parsing and generation, and to imple~ ~aent )~nguistic knowledge in a declarative way u~ing a formMism based upon Functional Descriptions (FD). We have ales devvloped the parser and the g~ueratio~ module so that they share informa~ tion~ and knowledge bases as much as possible: they work on the same semazLtic dictionary and the same linguistic knowledge bases, except th~ they kave their own graznmar. We have also ires p|emented a tracking of semantic objects that have been f~istantiated during a dialogue session: the socalled Token History is provided for semantic refvrence and anaphor resolution during parsing and for pronoun production during generation. After introducing to Esteam-316, this paper de,cribelJ the ~nguistic knowledge bases required by SAGE, and then foctmes on the Generation Modnleo Sv.ctlon 4 explains how pronouns are handled. The last section is a brief evaluation of our present