The young boy is pretend playing with boxes.
A little girl runs through a drugstore.
A young boy cannot be a little girl as well. Also you cannot be pretend playing with boxes and running through a drugstore at the same time.
exists p1 s1 x1.(n_boy(x1) & a_young(s1) & Theme(s1,x1) & exists s2 x2 x3.((x1 = x2) & with(x2,x3) & n_box(x3) & n_playing(x2) & a_pretend(s2) & Theme(s2,x2)))
exists e1 s1 x1 x2.(through(e1,x2) & n_drugstore(x2) & Actor(e1,x1) & v_run(e1) & n_girl(x1) & a_little(s1) & Theme(s1,x1))