A nun on her cellphone.
The nun does not own a cellphone.
One can either not own a cellphone or own a cell phone.
exists x1 x2.(a_topic(x1) & on(x1,x2) & n_cellphone(x2) & of(x2,x1) & n_female(x1) & n_nun(x1))
exists x1.(n_nun(x1) & -exists e1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_own(e1) & n_cellphone(x2)))