An orchestra is assembled and waiting to begin playing.
the people are sitting in the room with no instruments
The people in the orchestra have instruments because they are waiting to play and not just sitting in a room with no instruments.
exists e1 e2 p1 s1 x1 x2 x3.(a_topic(s1) & subset_of(e2,s1) & Topic(e2,p1) & Actor(e2,x3) & v_wait(e2) & exists e3 p2.(exists e4.(Actor(e4,x3) & v_play(e4)) & Topic(e3,p2) & Actor(e3,x3) & v_begin(e3)) & n_thing(x3) & subset_of(x1,s1) & Theme(e1,x2) & v_assemble(e1) & (x1 = x2) & n_orchestra(x1))
exists e1 x1 x2.(n_room(x2) & n_people(x1) & -exists x3.(in(e1,x2) & with(x2,x3) & n_instrument(x3)) & Actor(e1,x1) & v_sit(e1))