This paper offers a descriptive analysis of an aspectual periphrasis in Xhosa (Bantu S41). The construction in question consists of a form of ya ‘go’ plus a verb in the subordinate imperfective paradigm. It is argued that this construction works at the level of actionality (“lexical aspect” or “aktionsart”), rather than constituting an aspectual operator sensu stricto. The overall actional profile of this verbal unit is that of a degree achievement () or directed activity (), i.e. a process of change along a property scale. This change is construed as involving a plurality of successive steps. The contribution of the lexical item and its arguments is that of a property scale and/or target state. Throughout the description remarkable semantic parallels to a structure-wise comparable construction in Spanish (Romance, Indoeuropean) are pointed out. These structural and semantic parallels have implications for an oft-mentioned grammaticalization path leading from a motion-based construction to a marker of progressive aspect (, among others). The description of the construction is complemented by a note on a frequent collocation with an instrumental infinitive of the same verb stem.