A dog jumps over a hurdle in the grass.
A dog jumping over a hurdle during a contest.
Just because the dog jumped a hurdle does not mean he's in a contest.
exists e1 x1 x2 x3.(n_grass(x3) & over(e1,x2) & in(x2,x3) & n_hurdle(x2) & Actor(e1,x1) & v_jump(e1) & n_dog(x1))
exists e1 x1 x2 x3 x4.(a_topic(x1) & during(e1,x4) & n_contest(x4) & over(e1,x3) & n_hurdle(x3) & Actor(e1,x2) & v_jump(e1) & (x1 = x2) & n_dog(x1))