A participant in a sporting event has landed on his head while holding the ball on a field of grass.
The sport is played on a hard court.
THere can be no field of grass in a hard court.
exists e1 e2 x1 x2 x3 x4 x5 x6 x7.(n_ball(x5) & while(e1,e2) & Theme(e2,x5) & Actor(e2,x1) & v_hold(e2) & on(x5,x6) & of(x6,x7) & n_grass(x7) & n_field(x6) & on(e1,x4) & n_head(x4) & of(x4,x1) & n_male(x1) & Actor(e1,x1) & v_land(e1) & in(x1,x2) & n_event(x2) & of(x2,x3) & n_sporting(x3) & n_participant(x1))
exists e1 s1 x1 x2.(n_sport(x1) & on(e1,x2) & n_court(x2) & a_hard(s1) & Theme(s1,x2) & Theme(e1,x1) & v_play(e1))