A worker walking down the street.
A man is walking as a form of exercise
A worker walking down a street doesn't have to be a man and doesn't mean it is for exercise.
exists e1 x1 x2 x3.(n_street(x3) & a_topic(x1) & down(e1,x3) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_worker(x1))
exists e1 x1 x2 x3.(as(e1,x2) & of(x2,x3) & n_exercise(x3) & n_form(x2) & Actor(e1,x1) & v_walk(e1) & n_man(x1))