Auxiliary Verb Constructions and Decategorialization in Gĩkũyũ

Gĩkũyũ (E.51) exhibits several verbs that can be used both as lexical verbs and as auxiliary verbs. We compare the lexical and auxiliary usages of four verbs and show that all auxiliary verb usages display uniform restrictions concerning valency-related morphology (object marking, voice morphology). We interpret these as signs of decategorialization. Furthermore, we compare the auxiliary verbs with other desemanticized verb usages – light verbs – and argue that they differ in that light verbs do not exhibit decategorialization (compared to the corresponding lexical verb). From this, we conclude that decategorialization is a valid criterion – at least in Gĩkũyũ – for distinguishing different types of desemanticized verbs.