For every χsubmodule N of M,there exists a direct summand K of M,such that K∩N=0,and KN is an essential submodule of M;
For every χsubmodule N of M,there exists a direct summand K of M,such that K∩N=0,and KN is an essential submodule of M;
对于模 M的任意一个χ-子模 N,存在模 K|M,使得 K∩ N =0 ,且 K N≤ e M;