Old English, Middle English, History of English, grammar, phonetics, lexicology, English for Academic Purposes.
Language history, medieval history, Old and Middle English syntax, word order change in Germanic and Romance, noun phrases in old Germanic languages (Old English, Old Norse, Old High German, Old Saxon, Gothic), corpus linguistics, corpus annotation, information structure.
Author of the book Fra englisc til English: et språk blir til, which is a popular account of the history of English aimed at a general audience.
Chair of the Norwegian Academic Council for English Studies.
Vice-President for Teaching for the International Society of the Linguistics of English.