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Numerical investigation of mode transition induced by fast particle transport in phase space on the EAST tokamak has been carried out by the global kinetic-magnetohydrodynamic (MHD) code M3D-K. Firstly, based on the fishbone instabilities observed on EAST, linear simulations show that the fishbone instability is excited at experimental value of beam ion pressure. When the beam ion pressure is increased to exceed a critical value, the low frequency fishbone transits to a beta-induced Alfvén eigenmode (BAE) with much higher frequency. Nonlinear simulations show that the frequency of the low frequency fishbone chirps up and down with corresponding hole-clump structures in phase space. In addition to the low frequency mode, the high frequency BAE is excited during the nonlinear evolution due to the fast particle redistribution in phase space. Secondly, Energetic Particle Modes (EPMs) have been observed in EAST neutral beam injection (NBI) plasma, and a transition from EPMs to toroidal Alfvén eigenmodes (TAEs) is found. Nonlinear simulations show that the EPM frequency chirps down, and then a TAE emerge due to the fast particle transport in phase space. Finally, fishbone instabilities characterized by mode numbers m/n = 1/1, 2/2 have been observed in EAST. Numerical simulations show that the m/n = 2/2 high frequency fishbone branch is linearly stable, but nonlinearly grows due to the coupling with the m/n = 1/1 low frequency fishbone branch. The m/n = 2/2 fishbone frequency is almost twice of the m/n = 1/1 fishbone, and both fishbone frequencies chirp down together. In addition, a BAE with m/n = 2/2 is observed in the late nonlinear stage of the simulation. Energetic particle nonlinearity is dominant for the m/n = 2/2 fishbone saturation and transition to BAE. These works all find the mode transitions of different modes induced by fast particle transport in phase space.