A brown dog in a field.
There were cats on the field
Answer: Cats and dogs cannot be in the same field.
exists s1 x1 x2.(a_topic(x1) & in(x1,x2) & n_field(x2) & n_dog(x1) & a_brown(s1) & Theme(s1,x1))
exists p1 x1 x3.(n_field(x3) & exists x2.((x1 = x2) & on(x2,x3) & n_cat(x2)))