A speedboat racer stands on his boat in the water.
A man sitting on a porch
Standing and sitting are different states of being.  A boat and a porch are different places.
exists e1 x1 x2 x3 x4.(n_water(x4) & on(e1,x3) & in(x3,x4) & n_boat(x3) & of(x3,x1) & n_male(x1) & Actor(e1,x1) & v_stand(e1) & n_racer(x1) & of(x1,x2) & n_speedboat(x2))
exists e1 x1 x2 x3.(a_topic(x1) & on(e1,x3) & n_porch(x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_man(x1))