premise: A boy and a girl walk through the city.
hypothesis: A boy and a girl are walking through a dirty city.
explanation_1: the city doesn't always mean  dirty city.
explanation_2: Not all cities are dirty.
explanation_3: The city the boy and girl are walking through may not be dirty.
premise_logic: exists s1 x1 x2 x3 x4.(n_city(x4) & a_topic(s1) & subset_of(x2,s1) & through(x2,x4) & n_walk(x2) & of(x2,x3) & n_girl(x3) & subset_of(x1,s1) & n_boy(x1))
hypothesis_logic: exists e1 s1 x1 x2 x3 x4.(through(e1,x4) & n_city(x4) & a_dirty(s1) & Theme(s1,x4) & Actor(e1,x1) & v_walk(e1) & subset_of(x3,x1) & n_girl(x3) & subset_of(x2,x1) & n_boy(x2))