Hello, do you want to ask about the level of Cui Guowen? Cui Guowen has a high level. Cui Guowen published the book Daoshu, and he is an expert in the study of the Book of Changes in Tsinghua University, especially Daoshu. The level is naturally high. Cui Guowen is the vice president of Tsinghua Old Science and Technology Workers Association (referred to as Tsinghua Old Association for Science and Technology), a national famous Yijing master, Professor Tsinghua University, the president of Tsinghua University President Student Club, and the vice president of MIT Alumni Association Beijing Branch. He used to be the vice president of Tsinghua University Institute of Continuing Education, the director of Tsinghua University Foreign Academic and Cultural Exchange Center, and the director of Tsinghua University Foreign Affairs Office. Visiting scholar of Massachusetts Institute of Technology (1978~ 1980), visiting scholar of University of California, Berkeley (1986~ 1987), visiting scholar of Hong Kong University (1997 ~1997).