An surfer airborne over a wave.
A surfer is in the ocean.
Although the surfer is over a wave that wave may not be in the ocean.
exists x1 x2 x3.(a_topic(x1) & over(x1,x3) & n_wave(x3) & n_airborne(x1) & of(x1,x2) & n_surfer(x2))
exists p1 x1 x2.(n_ocean(x2) & in(x1,x2) & n_surfer(x1))