A man in a choir robe is standing at a microphone while the choir sits behind him.
The robes are black.
Not all choir robes are black.
exists e1 p1 x1 x2 x3 x4.(exists e2.(behind(e2,x1) & Actor(e2,x3) & v_sit(e2)) & n_male(x1) & n_choir(x3) & n_choir(x3) & while(e1,p1) & at(e1,x4) & n_microphone(x4) & Actor(e1,x1) & v_stand(e1) & in(x1,x2) & n_robe(x2) & of(x2,x3) & n_man(x1))
exists s1 x1.(n_robe(x1) & Theme(s1,x1) & a_black(s1))