reserve G for _Graph;
reserve G2 for _Graph, G1 for Supergraph of G2;

theorem Th71:
  for G2, G1 for x being set holds
    (x in the_Vertices_of G2 implies x in the_Vertices_of G1) &
    (x in the_Edges_of G2 implies x in the_Edges_of G1)
proof
  let G2, G1;
  let x be set;
  G2 is Subgraph of G1 by Th61;
  hence thesis by GLIB_000:42;
end;
