A small boy is pulling a small utility trailer.
An elderly man is pulling a large utility trailer.
An elderly man is not a small boy. A trailer can't be both small and large.
exists e1 s1 s2 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_pull(e1) & n_trailer(x2) & of(x2,x3) & n_utility(x3) & a_small(s2) & Theme(s2,x2) & n_boy(x1) & a_small(s1) & Theme(s1,x1))
exists e1 s1 s2 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_pull(e1) & n_trailer(x2) & of(x2,x3) & n_utility(x3) & a_large(s2) & Theme(s2,x2) & n_man(x1) & a_elderly(s1) & Theme(s1,x1))