schematicity of a grammaticalizing construction involves an increase of the range of possible collocates. This collocational expansion is also known as host-class expansion (Himmelmann 2004), or increase of the type frequency of a construction. In addition, a grammaticalizing construction suffers a gradual decrease in compositionality (Traugott & Trousdale 2013). But what counts as a different type of a discourse-level construction? Should it only concern the internal formal makeup of the construction, or does it involve different functional (including pragmatic) properties? Does it concern varying characteristics of a broader dialogic conversational pattern? And related to this issue, how can its degree of compositionality be defined? So, the diachronic study of discourse-level constructions could certainly benefit from a thorough quantitative framework, including the application of advanced measures of productivity (Hilpert 2013: 203, 207; Goldberg 2019). Finally, another avenue for future research is represented by the challenges prosody poses for Construction Grammar. Croft & Cruise (2004: 247) already argue that constructions “are ‘vertical’ structures that combine syntactic, semantic and even phonological information (for the specific words in a construction as well as any unique prosodic features that may be associated with the construction)”, while Hoffmann (2013: 326) claims that constructions “as form-meaning pairings can also include information on their intonation”. Many previous studies (Marandin 2006, Sadat-Tehrani 2008, Sansiñena & Elvira García 2018, among others) argue in favour of the inclusion of intonation, specifically, as an inherent part of grammatical constructions. It has been noted that intonation is a distinctive parameter in several insubordinate constructions (Evans 2007; Schwenter 2016; Kawanachi 2010; Gras 2016; Elvira García, Roseano & Fernández-Planas 2017), a well-known discourse-level phenomenon. Sansiñena & Elvira García (2018) contribute to this discussion through the detailed analysis of a problematic aspect of Spanish grammar: the delimitation between free-standing que- constructions. These have different prosodic features including different intonation, duration and intensity, and the study claims that these formal features should be included alongside morphological, syntactic, semantic, pragmatic and discursive features in the description of constructions. In this line of analysis, it is of ultimate importance to take into account the intonational phonology of the language variety studied, in particular, the availability and distribution of intonational patterns, and which intonational patterns are compatible with what functions in discourse. In this line: what aspects of prosody, such as intonational contour, should we include as form features of constructions? What specific kind of features are relevant to determine the constructional status of specific patterns? More work on prosodic features of constructions, as well as on the methodologies that might help identify and distinguish them, is needed.

### References

Auer, P. (2011). ‘Online syntax and Construction Grammar: a perfect match? Some reflections on elliptical expansions.’ Paper Presented at the Workshop on Grammar and Interaction Revisited, Helsinki, March 10–12, 2011. Barðdal, J. (2008). Productivity: Evidence from case and argument structure in Icelandic, Vol. 8. Amsterdam: John Benjamins. Boas, H. C. (2003). A Constructional approach to resultatives (Stanford Monograph in Linguistics). Amsterdam/Philadelphia: John Benjamins.