Professor Liu has teach psychology since he came to the Central China Normal University.
A. determination to
B. been determined to
C. been determining to
D. determined to
网友回答
A. determination to
(答案→)B. been determined to
C. been determining to
D. determined to
解析：Since引导的时间状语从句强调主句谓语动词动作的持续性。