Two hockey players in a struggle on the ice.
No one is on the ice playing hockey today.
If two hockey players are on the ice, then somebody is on the ice. There cannot be no one and someone simultaneously.
exists x1 x2 x3 x4.(n_ice(x4) & a_topic(x1) & in(x1,x3) & on(x3,x4) & n_struggle(x3) & n_player(x1) & of(x1,x2) & n_hockey(x2) & card_eq_2(x1))
exists x2.(n_ice(x2) & -exists p1 x1.(exists e1 x3 x4 x5.(on(x1,x2) & Time(e1,x5) & n_today(x5) & Theme(e1,x4) & Actor(e1,x3) & v_play(e1) & n_hockey(x4) & (x2 = x3)) & n_one(x1)))