Abstract:This paper presents a comprehensive description of Therefrom the perspective of Three Conceptual Domainsas put forward in Sweetser (1990), and then analyzes its objective-subjective continuum involved in the three domains.The general function of There beconstruction is to indicate the existence of a new entity/concept, which is materialized in the three domains as "real-world existence" "epistemic existence" and "speech-act existence".The three existences manifest the evolution of therefrom objective to subjective axis.The subjectified Therefeatures speaker involvement, the function of grounding and "leftward movement".This is an effective indication of the unified unidirectionality in both semantic evolvement and syntactic change.