A surfer on a whiteboard catches a wave.
Someone is doing water sports.
To surf, you must be in the water catching a wave.
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_catch(e1) & n_wave(x3) & on(x1,x2) & n_whiteboard(x2) & n_surfer(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_sport(x2) & of(x2,x3) & n_water(x3) & n_person(x1))