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The recent studies show that the formation and evolution process(star,globular clusters,gas...)of the nearby galaxies are still not clear.In the PanDAS survey,over 400 deg2 field was observed(deep to 25.5 mag in g band)and very complicated substructures in the halo of M31 galaxy were discovered: nearly 30 dwarf satellite galaxies,dozens of halo globular clusters and extended clusters are distributed in the outer halo to~150 kpc from the center of M31.It is also found the two galaxies M31/M 33 were actually connected by the star and gas stream,which has been proved by the recent HI observations.It reveals the possible interactions between M31 and M33 galaxies and the giant star streams were produces by the strong tidal forces.The study shows that the M31/M 33 interaction is still going on in a few giga years.It can be seen that the galaxy-interactions are much more complicated than that we expect and such discoveries may change the understandings of the fundamental nature of the Universe.So,it is interesting to investigate the interaction(substructures),formation and evolution of M31/M 33 sub-group,which are the nearest two giant spirals in our Local Group.The globular/star cluster systems of the two galaxies are good tracers to study the dynamics of the giant star streams and the substructures.For this study,the Xinglong 2.16m/Lijiang 2.4m will be used for our spectroscopic observations.The radial velocities and Lick absorption-line indices can thus be measured from the spectroscopes and the ages,metallicities,extinctions and masses of the star clusters in both M31 and M33 galaxies can be fitted with the SSP models.These parameters will be used as the input physical parameters for the numerical simulations.