My main area of research is syntactic change. My research looks at the mechanisms of syntactic change, and tries to explain why certain syntactic changes are possible or impossible or why some seem to be more ‘natural’ than others, whether this is understood in terms of grammaticalisation paths, or in terms of cycles of change, or in terms of resetting syntactic parameters.
I am particularly interested in Celtic and Slavonic languages, and have worked on various aspects of the history of these languages, including word order change, the development of markers of negation and changes in patterns of agreement marking within the noun phrase.
My work tries to integrate historical linguistics with neighbouring disciplines such as syntactic theory and child language acquisition, in the belief that the mechanisms of language change can be best understood in a more general theoretical context. My research in historical linguistics currently focuses on cycles of change in the expression of negation (Jespersen's Cycle) and on directionality in syntactic change, particularly grammaticalisation and degrammaticalisation. I have recently been awarded an AHRC research grant to investigate The development of negation in the languages of Europe.
I also have research interests in synchronic syntactic theory, where I have worked on wh-constructions, noun phrases, word order and clitics, within minimalism and Principles and Parameters. I am currently working on null subjects in Welsh and Slavonic, as part of the Cambridge-Durham project on Null subjects and the structure of parametric variation.
I am interested in the use of electronic corpora in theoretical linguistics. I am involved in the digitisation of historical texts for use in research on the history of the Celtic and Slavonic languages. I am particularly involved with the encoding of Welsh texts, and was principal investigator on an AHRB-funded project to create A historical corpus of the Welsh language 1500-1850.