Musicians together in an orchestra.
The musicians are playing for an audience.
Orchestra musicians are not always playing, and do not always have an audience.
exists s1 x1 x2.(ne_nam_musicians(x1) & in(s1,x2) & n_orchestra(x2) & Theme(s1,x1) & a_together(s1))
exists e1 x1 x2.(n_musician(x1) & for(e1,x2) & n_audience(x2) & Actor(e1,x1) & v_play(e1))