| The first part of the thesis investigates some problems in Iatridou et al (2001)'s account of the perfect and summarizes three universal features of the perfect constructions in European languages. With cross-linguistic data, a revised version of Iatridou et al's proposal on the perfect is proposed. With the revised theory, the thesis explains many behaviors of the perfect constructions in English, French and German, especially the U-reading of perfect progressives in English and the functions of perfect-level universal quantifiers in English (always, ever since, at least since), French(toujours) and German (schon immer).The second part mainly deals with the temporal adverbial since a. In this part, we probe into the problems in Dowty (1979), Mittwoch (1988) and IAI's analyses of since-adverbials. Borrowing Dowty (1979) and IAI's ideas of perfect-level adverbials and eventuality-level adverbials, we define two types of temporal adverbials, i.e. frame-level adverbials and eventuality-level adverbials. With various language data, we argue that since-adverbials introduce a time frame/interval in which eventuality is evaluated or through which eventuality is observed. We also find that universally speaking, seit in German, depuis in French, desde in Spanish and many others are frame-level adverbials. Thus the feature of frame-level adverbials is the universal feature of these groups of temporal phrases. Unlike its counterparts in other languages, since is quite unique, for it can be used only in perfect constructions, hence a perfect-level adverbial. Following IAI, we put since-adverbials between PERF operator and Asp operator. The last part of the chapter deals with the semantics of since a and aims at the resolution of the complex U/E-ambiguity. With empirical evidence, we reject Mittwoch (1988) and IAI's lexical ambiguity approach and a-inclusive and a-exclusive distinction. Comparing the situation at a and the situation at u, we propose that the left end and right end of PTS in English is symmetrical and the PTS is on a sliding base on both ends. The semantic structure of since-adverbials is proposed at the end and an analysis in a new perspective on the complex U/E-ambiguity is put forward. |