A girl in a purple shirt feeding ducks
A boy is milking a cow.
The subject cannot be a girl and a boy simultaneously.
exists s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x2) & n_duck(x2) & of(x2,x4) & n_feeding(x4) & of(x2,x3) & n_shirt(x3) & a_purple(s1) & Theme(s1,x2) & n_girl(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_milk(e1) & n_cow(x2) & n_boy(x1))