A flight attendant is demonstrating safety devices.
A worker is on the plane
He refers to a flight attendant not a worker.
exists e1 x1 x2 x3 x4.(Theme(e1,x3) & Actor(e1,x1) & v_demonstrate(e1) & n_device(x3) & of(x3,x4) & n_safety(x4) & n_attendant(x1) & of(x1,x2) & n_flight(x2))
exists p1 x1 x2.(n_plane(x2) & on(x1,x2) & n_worker(x1))