A rapper in a black outfit is on stage.
The stage is for perfomers.
A rapper would be on a stage because they are a performer.
exists p1 s1 x1 x2.(exists x3.(on(x1,x3) & n_stage(x3)) & in(x1,x2) & n_outfit(x2) & a_black(s1) & Theme(s1,x2) & n_rapper(x1))
exists p1 x1.(n_stage(x1) & exists x2.(for(x1,x2) & n_perfomer(x2)))