The discourse functions of grammatical constructions explain an enduring syntactic puzzle

Each grammatical construction serves one or more communicative functions. To express a message, multiple constructions typically need to be combined, and this requires their functions to be reconcilable. Here we provide a large-scale test of the claim that people judge sentences to be unacceptable to the extent that the discourse functions of the combined constructions conflict. Ten base constructions are combined with 3 long-distance dependency constructions. Critically, the gradient notion of backgroundedness is operationalized in two ways, via a Negation task and a new Discourse task. Results (N=680) demonstrate that both backgroundedness measures predict acceptability judgments on combinations of constructions more than the base constructions used in the backgroundedness measures themselves. Acceptability ratings on two types of wh-questions and on relative clauses all correlate highly with one another, supporting the claim that these types of long-distance dependency all foreground an element in their domain.