A dog races through the woods.
A dog is chasing down a fox.
First sentence does not mention why the dog is racing in the woods but second one mentions it is chasing a fox
exists x1 x2 x3.(n_wood(x3) & a_topic(x1) & through(x1,x3) & n_race(x1) & of(x1,x2) & n_dog(x2))
exists e1 s1 x1 x2.(a_down(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_fox(x2) & n_dog(x1))