LIN Biao did not participate in the battles of Tingsi Bridge and Hesheng Bridge; LIN Biao and MAO Zedong knew each other at the meeting of discussing masses work which was held from the first ten days of May to mid-June, 1928. LIN Biao asked to go to the south of Shanxi province fighting as a guerilla, which constantly showed the repetition of his right deviation pessimistic mood in the new situation MAO Zedong commanded LIN Biao as president of the Red Army University, which was not "punishing" of LIN Biao, but the trust and high praise of him. MAO Zedong and LIN Biao had the relations of teacher and student and of companions at the period of democratic revolution. In the Cultural Revolution period, the relation between them is was "intimate cooperation" more than the need of their respecfive poutical ambition.