A person is jumping using rollerblades.
The person is a professional rollerblader.
The fact that a person is jumping using rollerblades doesn't imply professional rollerblader.
exists e2 e1 x1 x2.(for(e1,e2) & Theme(e2,x2) & Actor(e2,x1) & v_use(e2) & n_rollerblade(x2) & Actor(e1,x1) & v_jump(e1) & n_person(x1))
exists p1 x1.(n_person(x1) & exists s1 x2.((x1 = x2) & n_rollerblader(x2) & a_professional(s1) & Theme(s1,x2)))