A baby girl playing at a park.
A baby is playing in a park.
Playing at a park and in the park implies same situation.
exists e1 x1 x2 x3 x4.(a_topic(x1) & at(e1,x4) & n_park(x4) & Actor(e1,x3) & v_play(e1) & (x1 = x3) & n_girl(x1) & of(x1,x2) & n_baby(x2))
exists e1 x1 x2.(in(e1,x2) & n_park(x2) & Actor(e1,x1) & v_play(e1) & n_baby(x1))