A boy jumps on a stone footing next to a lake.
A boy sits by the lake.
jumps and sits are different activities
exists e1 e2 x1 x2 x3 x4.(on(e1,x2) & to(e2,x4) & n_lake(x4) & r_next(e2) & Actor(e2,x3) & v_foot(e2) & (x2 = x3) & n_stone(x2) & Actor(e1,x1) & v_jump(e1) & n_boy(x1))
exists e1 x1 x2.(n_lake(x2) & by(e1,x2) & Actor(e1,x1) & v_sit(e1) & n_boy(x1))