A black dog is carrying a white dog toy through a field of high grass.
No dogs in the grass.
Either there is a  black dog or no dog and cannot be both
exists e1 s1 s2 s3 x1 x2 x3 x4 x5.(through(e1,x4) & of(x4,x5) & n_grass(x5) & a_high(s3) & Theme(s3,x5) & n_field(x4) & Theme(e1,x2) & Actor(e1,x1) & v_carry(e1) & n_toy(x2) & of(x2,x3) & n_dog(x3) & a_white(s2) & Theme(s2,x2) & n_dog(x1) & a_black(s1) & Theme(s1,x1))
exists x2.(n_grass(x2) & -exists x1.(a_topic(x1) & in(x1,x2) & n_dog(x1)))