A choir, in spotlight, standing in a semi-circle, being lead by a conductor, who is in shadow in front of the choir, and wearing a gray and black striped shirt and black pants
An a capella group is getting ready to perform in front of a massive audience.
Not all choirs are acapella.  Some use instruments while they sing.  The choir may not be getting ready to perform, they could be leaving the stage at the end of a performance.  The choir may not be singing for a massive audience, they could be practicing in an empty room.
exists e1 e2 p1 p2 s1 s2 s3 s4 x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11 x12.(Theme(e2,x10) & Actor(e2,x8) & v_wear(e2) & subset_of(x12,x10) & n_pants(x12) & a_black(s4) & Theme(s4,x12) & subset_of(x11,x10) & n_shirt(x11) & a_striped(s3) & Theme(s3,x11) & a_black(s2) & Theme(s2,x11) & a_gray(s1) & Theme(s1,x11) & in(x8,x9) & n_spotlight(x9) & n_choir(x8) & by(p1,x6) & exists x14 x15.(in(x7,x14) & in(x14,x15) & of(x15,x1) & n_front(x15) & n_shadow(x14)) & n_choir(x1) & n_choir(x1) & (x6 = x7) & n_conductor(x6) & exists x13.((x4 = x13) & n_lead(x13)) & in(x4,x5) & n_spotlight(x5) & n_choir(x4) & in(e1,x3) & n_semi-circle(x3) & Actor(e1,x1) & v_stand(e1) & in(x1,x2) & n_spotlight(x2))
exists e1 p1 x1 x2.(exists p2 s1.(Topic(s1,p2) & Actor(s1,x1) & a_ready(s1) & exists e2 s2 x3 x4.(in(e2,x3) & of(x3,x4) & n_audience(x4) & a_massive(s2) & Theme(s2,x4) & n_front(x3) & Actor(e2,x1) & v_perform(e2))) & Topic(e1,p1) & Actor(e1,x1) & v_get(e1) & n_group(x1) & of(x1,x2) & n_capellum(x2))