A girls is jumping in the sand.
Someone jumps in sand.
girl is someone. jumping refers to jumps.
exists e1 x1 x2.(n_sand(x2) & in(e1,x2) & Actor(e1,x1) & v_jump(e1) & n_girl(x1))
exists x1 x2.(a_topic(x1) & in(x1,x2) & n_sand(x2) & n_jump(x1))