Stage/individual-level predicates, topics and indefinite subjects

Unlike Erteschik-Shir (1997) and de Swart (1999), we argue that the so-called Davidsonian arguments both in stage-level and individual-level predicates are able to function as topics, namely, existential stage topics and generic situation topics, respectively, which conforms with the well-known definiteness topic constraint. These two types of topics, however, are available only when the Davidsonian argument is bound via different means: the former gets bound in the existential domain, while the latter is constrained by the generic operator. Concerning the situation variable constrainer in sentences with individual-level predicates, we argue that besides general additional information, like adverbials 'usually' in English, 'tongchang'/'yibande', 'yaoshi... jiu' (if... then), etc, in Mandarin, bare NPs with kinddenoting and predicates denoting inherent property will help accommodate the generic operator, and thus a generic situation topic is available and sentences with indefinite subject NPs and individual-level predicates thus get licensed. As a consequence, we suggest that the necessary condition for the indefinite subject sentence should be that the indefinite subject NP is interpreted as specific or a stage topic/generic situation topic is available.