The rear end of an animal whose front end is underground.
A animal digging
The animal may not be digging.
exists s1 s2 s3 x1 x2.(a_topic(x1) & of(x1,x2) & Theme(s3,x1) & a_underground(s3) & n_end(x1) & n_end(x1) & a_front(s2) & Theme(s2,x1) & of(x1,x2) & n_animal(x2) & a_rear(s1) & Theme(s1,x1))
exists x1 x2.(a_topic(x1) & n_digging(x1) & of(x1,x2) & n_animal(x2))