A man is working on his wooden boat.
He is a carpenter by trade.
A man can work on a wooden boat and not be a carpenter.
exists e1 s1 x1 x2.(on(e1,x2) & n_boat(x2) & a_wooden(s1) & Theme(s1,x2) & of(x2,x1) & n_male(x1) & Actor(e1,x1) & v_work(e1) & n_man(x1))
exists p1 x1.(n_male(x1) & exists x2 x3.((x1 = x2) & by(x2,x3) & n_trade(x3) & n_carpenter(x2)))