The relation between head movement and periphrasis

In joint work with Asia Pietraszko, I've been investigating the relation between head movement and the synthesis-periphrasis distinction in the verbal domain. We use the term "synthesis" to refer to verbal expressions in which the lexical verb bears all the verbal inflection in a clause (e.g. "rode" in English). In contrast, a periphrastic verbal expression additionally contains an auxiliary verb (specifically, "be" or "have"), and verbal inflection is distributed between the lexical verb and the auxiliary (e.g. "had ridden").

We argue for two crosslinguistic generalizations: Complex Head Optionality (CHO) and *V-Aux. According to CHO, languages vary as to whether tense (and agreement) inflection forms a complex head (=word) with a verb. *V-Aux states that the lexical verb and the auxiliary are never part of the same complex head. Existing analyses of periphrasis can account for one or the other generalization, but not for both.

We further argue that this tension between the two generalizations is resolved if we adopt the hypothesis that both head movement and periphrasis are tied to selection. More specifically, we propose that head movement is parasitic on a selectional relation (following Svenonius 1994, Julien 2002, Matushansky 2006, and Preminger 2019) and that periphrasis is Merge of an auxiliary verb triggered by a selectional feature of a functional head that's not satisfied by the lexical verb (Déchaine 1995, Cowper 2010, Pietraszko 2017).