ABSTRACT
Case is a syntactic, semantic and morphological system that marks the functions of noun phrases in a sentence. This chapter focuses on case assignment and case alternations that are semantically based, as in Differential Subject Marking (DSM) and Differential Object Marking (DOM), the phenomena in which ergative, dative, and accusative case marking are conditioned by such factors as transitivity, perfectivity, animacy, specificity, and discourse prominence. Syntactic analyses capture the structural prominence of these arguments by projecting them in functional projections higher than the projections for unmarked objects. Several studies of very young children acquiring a variety of morphologically complex languages show that semantically conditioned cases are acquired by age three. Yet, the phenomenon is quite challenging for L2 learners, especially if the L1 does not mark cases overtly. Semantically based case is also vulnerable in heritage language acquisition. This chapter synthesizes the latest research on this topic and points to directions for future research.
