The principal syntactic function of the clause element of adverbial is to modify a VP which describes an event (stative or active), and most adverbials, except for adverbials of modality, describe states. We claim that the position of adverbials with regard to the VP is mainly controlled by the three conceptual principles proposed by Tai (1985: 214): the Principle of Temporal Sequence (PTS), the Principle of Temporal Scope (PTSC) and the Principle of Whole-Before-Part. The PTSC will be introduced as our discussion proceeds to temporal adverbials. The PTS, for the sake of clarity and convenience, is reintroduced as follows:
“The relative order between syntactic units is determined by the temporal order of the states they represent in the conceptual world.”
 Loar, J. K. (2011). Chinese syntactic grammar: functional and conceptual principles. New York: Peter Lang.