a rock climber
a person climbing rocks
A rock climber is a person climbing rocks.
exists x1 x2.(a_topic(x1) & n_climber(x1) & of(x1,x2) & n_rock(x2))
exists e1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_climb(e1) & n_rock(x3) & (x1 = x2) & n_person(x1))