A man piloting behind the wheel of a boat.
A man drives a boat.
A person piloting a vehicle drives it.
exists e1 x1 x2 x3 x4.(n_wheel(x3) & a_topic(x1) & behind(e1,x3) & of(x3,x4) & n_boat(x4) & Actor(e1,x2) & v_pilot(e1) & (x1 = x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_drive(e1) & n_boat(x2) & n_man(x1))