a dog chilling on a bench while he has two biker observing him
A dog is on the bench at the park.
The dog could be sitting on a bench anywhere, there is nothing in the first sentence to imply that he is at the park.
exists e1 p1 x1 x2 x3.(a_topic(x1) & exists e3 e2 x1 x4 x5.(Theme(e3,x4) & Actor(e3,x1) & v_have(e3) & Theme(e2,x1) & Actor(e2,x5) & v_observe(e2) & n_male(x1) & (x4 = x5) & n_biker(x4) & card_eq_2(x4)) & n_male(x1) & while(e1,p1) & on(e1,x3) & n_bench(x3) & Actor(e1,x2) & v_chill(e1) & (x1 = x2) & n_dog(x1))
exists p1 x1 x2 x3.(n_park(x2) & n_bench(x3) & at(p1,x2) & on(x1,x3) & n_dog(x1))