A crowd watching air balloons at night.
There are 20 balloons in the air and 50 on the ground.
We cannot tell how many balloons are in the air or in the ground.
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & at(e1,x5) & n_night(x5) & Theme(e1,x3) & Actor(e1,x2) & v_watch(e1) & n_balloon(x3) & of(x3,x4) & n_air(x4) & (x1 = x2) & n_crowd(x1))
exists p1 x1 x2 x3 x4 x5.(n_ground(x5) & n_thing(x4) & card_eq_50(x4) & n_air(x3) & subset_of(x4,x2) & subset_of(x3,x2) & on(p1,x5) & in(p1,x2) & exists x6.((x1 = x6) & n_balloon(x6) & n_date(x6) & a_date_day_20(x6) & a_date_day_20(x6)))