Discourse Processing in MT: Problems in Pronominal Translation

1. Intrcnluction Translation of anaphoric expressions has been problematic in most of the MT systems (Key 1986). One ot' the main reasons for the difficulties lies in the lack of discourse information representation in the MT systems. In this paper, we report an implementation of the Discourse Representation Theory in an LFG-based Engl ishto-Japanese MT program, and discuss problems in translating anaphoric expressions in this system. 2. Problems in Translating Anaplmra Problems in translation of anaphoric expressions can be seen on three different but interactive levels of l inguistic information: lexical, syntact ic and pragmatic. The main problem on the lexical level is due to a difference in the language specific parameters in the pronominal system such as F features (person, gender, number, etc.). Surface forms of pronominals depend on the F features of their antecedents, so that the translation of a particular pronominal form cannot be determined sorely by the pronominal itself. For example, 'ship' in English is feminine, but its translation, 'hune', is neutral in Japanese. Thus, a preform 'she' for 'ship' should not be translated as 'kanojo' (3rd, sing, fem), but as 'sore' (3rd, sing, neut). Problems on the syntactic level are mainly due to a difference in the distribution of anaphoric expressions. Mapping relations between English pronominals and their Japanese counterparts are shown below: