A big dog tied to a door.
A puppy is tied to a door.
Just because it is a dog doesn't mean it is a puppy.
exists e1 s1 x1 x2 x3.(a_topic(x1) & to(e1,x3) & n_door(x3) & Theme(e1,x2) & v_tie(e1) & (x1 = x2) & n_dog(x1) & a_big(s1) & Theme(s1,x1))
exists e1 x1 x2.(to(e1,x2) & n_door(x2) & Theme(e1,x1) & v_tie(e1) & n_puppy(x1))