This is  my recent joint work with Fan and Tam. in the talk，we will study the limiting behavior the Brown-York mass of the coordinate spheres in an asymptotically flat manifold. Limiting behavior of volumes of regions related to coordinate spheres is also obtained. We will also study expansions of the Brown-York mass and the Hawking mass of geodesic spheres with center at a fixed point $p$ of a three manifold. Some geome tric consequences will be derived.