A girl is sitting on the side of a mountain.
Two men are working outside.
The subject cannot be a girl and two men
exists e1 x1 x2 x3.(n_side(x2) & on(e1,x2) & of(x2,x3) & n_mountain(x3) & Actor(e1,x1) & v_sit(e1) & n_girl(x1))
exists e1 s1 x1.(a_outside(s1) & Manner(e1,s1) & Actor(e1,x1) & v_work(e1) & n_man(x1) & card_eq_2(x1))