A man crouching and holding a camera.
Nobody is crouching.
A man is crouching, but then nobody is crouching. Either someone is crouching or no one is at all.
exists e1 s1 x1 x2 x3 x4.(a_topic(s1) & subset_of(e1,s1) & Theme(e1,x4) & Actor(e1,x3) & v_hold(e1) & n_camera(x4) & n_thing(x3) & subset_of(x1,s1) & n_crouching(x1) & of(x1,x2) & n_man(x2))
-exists e1 x1.(Actor(e1,x1) & v_crouch(e1) & n_person(x1))