At school, he was called one of the "Four Famous Arrests" because he was strict with his students. The doctoral student he took said that "he has a large vocabulary and criticizes students for not paying attention to samples"; But he also spared no effort to worry about papers and homework for students. Knowing that he was suffering from cancer, the first thing Liu Pujiang did was to sort out books and notes and let the students continue to do what they had not finished. Ask the students to point out which books are useful ... A student who can't sleep at night sent a short message to Liu Pujiang: I will try my best to finish your unfinished research. He replied: "It is the greatest comfort for me that my unfinished business has been handed down."