an old lady walks down the street.
A person is on a street.
A lady is a person. In order to walks down the street, the person must be on the street.
exists e1 s1 x1 x2.(n_street(x2) & down(e1,x2) & Actor(e1,x1) & v_walk(e1) & n_lady(x1) & a_old(s1) & Theme(s1,x1))
exists p1 x1.(exists x2.(on(x1,x2) & n_street(x2)) & n_person(x1))