Several hockey players from different teams and a referee are together on the ice.
Some players and a referee are preparing to play hockey.
Just because there are hockey plays and a referee are together, does not mean they are preparing to play hockey.
exists s1 s2 x1 x2 x3 x4 x5 x6 x7.(n_ice(x7) & n_team(x5) & on(s2,x7) & Theme(s2,x1) & a_together(s2) & from(x1,x3) & subset_of(x6,x3) & n_referee(x6) & subset_of(x4,x3) & -(x4 = x5) & n_team(x4) & n_player(x1) & of(x1,x2) & n_hockey(x2) & a_several(s1) & Theme(s1,x1))
exists e1 p1 x1 x2 x3.(Topic(e1,p1) & Actor(e1,x1) & v_prepare(e1) & exists e2 x4.(Theme(e2,x4) & Actor(e2,x1) & v_play(e2) & n_hockey(x4)) & subset_of(x3,x1) & n_referee(x3) & subset_of(x2,x1) & n_player(x2))