1.With a new method, more briefly than [1]69 we prove. THEOREM 1 A lattice L is a modularlattice iff the sublattice L_1~ generated by arbitrary two sequences a=c_0lattice.
2.In this paper, it is shown that the mapping ρ|?ctr ρ is a complete homomorphism of the strong P congruence lattice of S(P) onto the lattice of normal equivalences on P , and that the congruence θ induced by it has all its classes complete modular lattices.
