A skier does a jump in front of an empty chair lift.
A snowboarder is on the ground next to a crowd of people.
A skier can't be a snowboarder at the same time, and someone who does a jump is in the air, not on the ground.
exists e1 s1 x1 x2 x3 x4 x5.(Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & of(x2,x4) & n_lift(x4) & of(x4,x5) & n_chair(x5) & a_empty(s1) & Theme(s1,x4) & in(x2,x3) & n_front(x3) & n_jump(x2) & n_skier(x1))
exists p1 x1 x2.(n_ground(x2) & exists x3 x4 x5.(on(x1,x2) & to(x3,x4) & of(x4,x5) & n_people(x5) & n_crowd(x4) & next(x2,x3) & n_thing(x3)) & n_snowboarder(x1))