In this paper we have discussed the SU3 and G2 transformation properties of the weak interactions. By assuming selection rules for certain operators in SU3 different from isospin, a series of relations between the amplitudes of the nonleptonic decays of the strange particles are obtained, which include some results obtained in previous works. Assuming the G2 symmetry of the strong interactions, we discuss the selection rules in these processes in a similar manner and show that the weak interactions cannot transform according the representations 7 or 14 of G2.