A group of spectators are watching a choir performance.
The choir is singing.
A choir performs by singing.
exists e1 x1 x2 x3 x4.(Theme(e1,x3) & Actor(e1,x1) & v_watch(e1) & n_performance(x3) & of(x3,x4) & n_choir(x4) & of(x1,x2) & n_spectator(x2) & n_group(x1))
exists e1 x1.(n_choir(x1) & Actor(e1,x1) & v_sing(e1))