This research aims to investigate the mechanisms and tendencies of grammaticalization when the verb was transformed to ”Te” auxiliary verb by the changes of syntactics, semantics, morphology and phonology. By analyzing these changes of grammatical processes, we can find that the case markers in syntactic construction show separation or variation; furthermore, the semantic bleaching, contraction and accent change are also seen in the transformation processes. Hence, the grammatical tendencies of ”Te” auxiliary verb can be induced as three categories: (ⅰ). extension to the same domain; (ⅱ). extension to a similar domain; (ⅲ). extension from the non-concrete space domain to the time domain.