Abstract: The standard model in particle physics implies some contradictions on symmetries.The three generations of quarklepton deviate from the SU(3) symmetry,and should form six symmetrical SU(2)groups.According to the complete symmetry,on the analogy of an isospin doublet ud(I=1/2),we obtain various symmetrical isospin doublets:cs,tb,and three generations of lepton (ve-e,vμ-μ,vτ-τ).But it differs from that s and c quarks are two isospin singles (I=0).We introduce a new composite quantum number F=IS,which c...