Group of people play music on stage together.
There is a concert in progress.
WE DON'T KNOW THAT IT IS A CONCERT.
exists e1 s1 x1 x2 x3 x4.(ne_org_group(x1) & a_together(s1) & Manner(e1,s1) & on(e1,x4) & n_stage(x4) & Theme(e1,x3) & Actor(e1,x1) & v_play(e1) & n_music(x3) & of(x1,x2) & n_people(x2))
exists p1 x1 x2 x3.((x1 = x2) & in(x2,x3) & n_progress(x3) & n_concert(x2))