This book presents an innovative analysis of topic and subject markings in Japanese in relation to temporal and aspectual interpretations of clauses. It delineates two distinct types of tense/aspect interpretations correlated with wa- and ga-marked subjects in terms of two types of (i) evaluation time, (ii) Reference time, and (iii) viewpoint aspect. In order to provide syntactic mechanisms to account for this correlation between wa- and ga-markings of ''subjects'' and the two distinct types of tense/aspect interpretations, the author proposes two subdivisions of Tense as functional categories (above VP) in the articulated phrase structure of a sentence. They are postulated to contain distinct semantic features, both T[ense]- and D[eterminer]-features that get checked by predicates and subject DPs respectively. This work draws important connections between the Japanese facts and aspects of the grammars of other languages such as the syntax and semantics of stage- and individual-level predicates and the tense system. Every chapter is informative, insightful, and generally ground-breaking. This book sets the new standard for work on this topic.