A person hanging off of a cliff.
Someone is standing upside down on their hands.
A person cannot be hanging off a cliff and also standing upside down on their hands.
exists e1 x1 x2 x3.(a_topic(x1) & of(e1,x3) & n_cliff(x3) & r_off(e1) & Actor(e1,x2) & v_hang(e1) & (x1 = x2) & n_person(x1))
exists e1 s1 s2 x1 x2.(on(e1,x2) & n_hand(x2) & of(x2,x1) & n_thing(x1) & a_down(s2) & Manner(e1,s2) & a_upside(s1) & Manner(e1,s1) & Actor(e1,x1) & v_stand(e1) & n_person(x1))