A lead choir singer with the rest of the choir singing in the background of a concert hall.
A singing group is performing acapella style
Jut because, the choir is singing does not imply that they are performing acapella style.
exists e1 s1 x1 x2 x3 x4 x5 x6 x7.(n_background(x5) & n_rest(x3) & a_topic(x1) & with(x1,x3) & of(x3,x2) & in(e1,x5) & of(x5,x6) & n_hall(x6) & of(x6,x7) & n_concert(x7) & Actor(e1,x4) & v_sing(e1) & (x2 = x4) & n_choir(x2) & n_choir(x2) & n_singer(x1) & of(x1,x2) & a_lead(s1) & Theme(s1,x1))
exists e1 s1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_style(x2) & of(x2,x3) & n_acapellum(x3) & n_group(x1) & a_singing(s1) & Theme(s1,x1))