Woman on airplane models a flotation device.
The woman is working as a stewardess.
Not all stewardess models a flotation device.
exists x1.(ne_nam_woman(x1) & all x3 x2.((n_device(x2) & of(x2,x3) & n_flotation(x3)) -> exists x4 x5.(a_topic(x1) & on(x1,x4) & for(x4,x2) & n_model(x4) & of(x4,x5) & n_airplane(x5))))
exists e1 x1 x2.(n_woman(x1) & as(e1,x2) & n_stewardess(x2) & Actor(e1,x1) & v_work(e1))