'What and then a little robot brings it to you?': The reactive what-x construction in spoken dialogue

In the process of compiling a new corpus of contemporary spoken British English, the London-Lund Corpus 2, we hit upon a construction used in the conversations recorded that had not previously been dealt with in the literature, namely the reactive what-x construction. Prompted by this discovery, we carried out a detailed analysis of its properties and constraints within the broad framework of Cognitive Linguistics, namely Construction Grammar, and found that the reactive what-x construction features the interrogative what directly followed by a phrasal or clausal complement x. Moreover, what forms one tone unit with the complement and never carries a nuclear pitch accent. The core meaning is to signal an immediate reaction to something said by another speaker in the preceding turn, and the dialogic functions include questions proper as well as expressions of disagreement. The two contributions of this article are: (i) to provide a definition of the reactive what-x construction and (ii) to propose a crucial theoretical extension of Construction Grammar involving a broadening of the concept of construction to cover not only the lexical-semantic pairing but also prosodic properties and the role of the construction in the interactive dialogic space in speech.