Constructions are abstractions of resources we have available as ways of expressing ourselves. The study argues for the feasibility of seeing constructions as flexible prototypes in terms of which we categorize the world: constructions have few if any necessary and sufficient conditions that are always applicable. As support for this view, an analysis of the correlative TatT-construction in English is carried out, indicating that even if we can set up a dozen characteristics of the construction, none of them are necessary for an expression to be characterized as an instance of the construction. Furthermore, for constructional analyses to be truly usage-based, variations within prototypes have to be explicated. A Construction Discourse approach is used to show how pragmatic and discourse factors can distinguish and afford particular meanings and functions to non-prototypical instances of a construction.
