Is I think a Discourse Marker
I. Mindt, in: E. Mengel, H.-J. Schmid, M. Steppat (Eds.), Anglistentag 2002 Bayreuth. Proceedings of the Conference of  	the German Association of University Teachers of English, Volume XXIV, Wissenschaftler Verlag, Trier, 2003, pp. 473–483.