A guitar band is playing on stage.
A jazz pianist plays a concert at the Acropolis.
It can be either a guitar band or jazz pianist playing on stage.
exists e1 x1 x2 x3.(on(e1,x3) & n_stage(x3) & Actor(e1,x1) & v_play(e1) & n_band(x1) & of(x1,x2) & n_guitar(x2))
exists e1 x1 x2 x3 x4.(ne_geo_acropolis(x4) & at(e1,x4) & Theme(e1,x3) & Actor(e1,x1) & v_play(e1) & n_concert(x3) & n_pianist(x1) & of(x1,x2) & n_jazz(x2))