1.Foliation of 3-dimensional space forms by surfaces with constant mean curvature. 2.Manifolds with pure non-negative curvature operator. 3.A lower bound for the eigenvalue of a finite-volume negative curved manifold. 4.The generalized gauss map of minimal surfaces in H3 AND H4. 5.Spherical surfaces with constant mean curvature in hyperbolic space. 6.Correction of complete hypersurfaces in the space form with three principal curvatures.