This paper deals with the semantics of two discourse markers, viz. French en fait (“in fact”) and Dutch eigenlijk (“actually”), commonly associated with the expression of “opposition” and “reformulation”. A special focus lies on methodological issues in the description of such markers, since their non-propositional meanings seem to require what is called a ‘combined corpus approach’, including written and spoken comparable data as well as translation corpora. It is argued that eigenlijk and en fait are best described as adversatives, at the intersection of “opposition” and “reformulation” which constitute their basic meanings, and from which other meanings such as “causality”, “counterexpectation”, “enhancement” and “attenuation” can be inferred. Evidence from all sets of corpora moreover suggests that it is the semantic underspecification of en fait and (especially) eigenlijk which ultimately accounts for their high level of polysemy.