This is a professional fisherman.
A professional fisherman.
To say this is a professional fisherman, it must involve a professional fisherman.
exists p1 x1.(n_thing(x1) & exists s1 x2.((x1 = x2) & n_fisherman(x2) & a_professional(s1) & Theme(s1,x2)))
exists s1 x1.(a_topic(x1) & n_fisherman(x1) & a_professional(s1) & Theme(s1,x1))