Frontiers of Multilingual Grammar Development

Abstract

The thesis explores a number of ways for developing multilingual grammars written in GF (Grammatical Framework). The goal is to enhance both the coverage of the grammars, in terms of content and number of languages, and to reduce the development effort by automating a larger part of the process.

The first direction in grammar development targets the creation of general language resources. These are the starting point for building domain-specific grammars for the language. Developing resource grammars gives a good overview of the effort required and provides a solid base for subsequent experiments in automation. Our work resulted in building computational grammars for Romanian and Swedish.

A further development step is multilingual domain-specific grammar creation. The technique we employed is converting structured models into grammars, which preserves the original structure of the model as a backbone of the grammar and uses the general GF resources for a smooth multilingual verbalization of the model. The use cases considered are an upper-domain ontology, a business model and an ontology describing cultural heritage artefacts, each posing a different challenge and illustrating another aspect of the GF grammars-ontology interoperability and its advantages.

An orthogonal approach to multilingual grammar development aims at increasing the number of languages from a domain grammar. Our solution is an example-based prototype which partially replaces grammar programming with feedback from native informants and SMT tools (such as Google Translate).

Last but not least, as an attempt to not only enhance GF grammars, but also use them in a novel way, we present the grammar-based hybrid system architecture combining GF grammars and SMT systems. This marks some of the first steps in using grammars for translating free text. As a side-effect of the work, we propose a technique for building bilingual GF lexicon resources from SMT phrase tables.