Revisiting the acquisition of Sesotho noun class prefixes

The issue of how and when Sesotho noun class prexes are acquired was the topic of a seminar Dan and I taught while I was a postdoctoral fellow at UC Berkeley from 1983-1985. Since Bantu languages have multiple singular and plural noun class prexes, this was a topic of particular theoretical interest for Dan given his Operating Principles of paying attention to the beginnings and ends of words, and unique form-function mapping (Slobin 1973, 1985). The preliminary investigation of how Sesotho noun class prexes are learned did not support these Operating Principles, with multiple singular and plural prexes appearing gradually between the ages of 2 and 3 (Demuth, 1988). This chapter reports on recent research examining the noun class input Sesotho-speaking children actually hear. In so doing, it also provides insight into the grammatical structure of Sesotho, how it differs from other Bantu languages, and the learnability issues that arise. Equipped with this background it is now possible to better understand the apparent ‘gradual’ nature of the acquisition process, and to develop a more ne-grained model of how language learning takes place.