Keller considers semi-fixed expressions that occur in a corpus of North American English discourse, like 'the main point is', 'I have something to add to that', or 'what I really said is this'. K. calls them 'gambits'. On the basis of some 500 such gambits, an initial subdivision is offered which distinguishes four main functions: semantic framing, social signalling, state-of-consciousness signalling, and communicative signalling. These functions are illustrated with a stretch of discourse recorded from a television talk show.