A boy is attempting to climb an iron fence.
The fence is iron.
If it is an iron fence, it is made of iron.
exists e1 p1 x1.(Topic(e1,p1) & Actor(e1,x1) & v_attempt(e1) & exists e2 x2 x3.(Theme(e2,x2) & Actor(e2,x1) & v_climb(e2) & n_fence(x2) & of(x2,x3) & n_iron(x3)) & n_boy(x1))
exists p1 x1.(n_fence(x1) & exists x2.((x1 = x2) & n_iron(x2)))