A construction worker hard at work.
A person is working.
A person is working implies he is construction worker.
exists s1 x1 x2 x3 x4.(a_topic(x1) & at(s1,x4) & n_work(x4) & Theme(s1,x3) & a_hard(s1) & (x1 = x3) & n_worker(x1) & of(x1,x2) & n_construction(x2))
exists e1 x1.(Actor(e1,x1) & v_work(e1) & n_person(x1))