The GF Resource Grammar Library

The GF Resource Grammar Library is a set of natural language grammars implemented in GF (Grammatical Framework). These grammars are in a strong sense parallel: they are built upon a common abstract syntax, i.e. a common tree structure. Individual languages are obtained via compositional mappings from abstract syntax trees to feature structures specific to each language. The grammar defines, for each language, a complete set of morphological paradigms and a syntax fragment comparable to CLE (Core Language Engine). It is available as open-source software under the GNU LGPL License. The current coverage is fourteen languages: Bulgarian, Catalan, Danish, English, Finnish, French, German, Italian, Norwegian (bokmål), Polish, Romanian, Russian, Spanish, and Swedish. More languages are under construction. The library can be used as a resource for language processing tasks, such as translation, multilingual generation, software localization, natural language interfaces, and spoken dialogue systems. The library may also have some language-typological interest as an experiment showing how much grammatical structure can be shared between languages. The focus of this paper is on the linguistic aspects of the library—in particular, what syntactic structures are covered and how the problems arising in different languages have been solved. We will also discuss the nature of the common abstract syntax with respect to translation equivalence.

Source authoring for multilingual generation of personalised object descriptions

We present the source authoring facilities of a natural language generation system that produces personalised descriptions of objects in multiple natural languages starting from language-independent symbolic information in ontologies and databases as well as pieces of canned text. The system has been tested in applications ranging from museum exhibitions to presentations of computer equipment for sale. We discuss the architecture of the overall system, the resources that the authors manipulate, the functionality of the authoring facilities, the system's personalisation mechanisms, and how they relate to source authoring. A usability evaluation of the authoring facilities is also presented, followed by more recent work on reusing information extracted from existing databases and documents, and supporting the OWL ontology specification language.

Nuclear transitivity in English and Spanish

This paper presents a contrastive overview of nuclear transitivity in English and Spanish from a systemic-functional perspective. The study attempts to achieve two main goals. Firstly, we investigate the usefulness of the transitive/ergative distinction developed by Davidse (1992) for material processes in English, when applied to different process types in both English and Spanish. Secondly, we attempt to provide a fine-grained specification of these linguistic resources which might form the basis for computational treatment in the applied context of Multilingual Generation (MLG), the automatic production of texts in various languages from a single underlying data source. We first review the specifications provided for English in the computational grammar Nigel (Mann 1983; Matthiessen 1988; Matthiessen and Bateman 1991), and in the extensive reference grammar developed by Matthiessen (1995), showing that, though useful for practical generation purposes, they conflate the notions of agency and causation under the same system. These specifications thus blur the transitive/ergative distinction, which is also fundamental to observe how semantically related verbs may behave differently in English and in Spanish (Lavid and Arús 1998a, 1998b; Arús and Lavid 2001). We propose, instead, a model of nuclear transitivity consisting of three simultaneous systems: a system of agency (concerned with the presence or absence of the feature Agent), a system of process type (concerned with the semantic type of process involved), and a system of causation (concerned with the variable of instigation). This latter system establishes the paradigmatic distinction between transitive and ergative processes which we claim to be fundamental for an accurate contrastive description of English and Spanish. It is expected that the proposed model, which captures the common semantic potential of nuclear transitivity in English and Spanish, will prove useful as the linguistic basis for a more detailed computational specification in the context of MLG.

The Realization of Individual Instances in a Multilingual Generation System

This paper presents multilingual sentence generation in the GENESE project, part of the efforts to develop pivot-language based machine translation. The handling of individual instances will be developed and the problem of mass expressions will be highlighted. This will illustrate the use of available linguistic theories for the generation of individual instances in GENESE.