A young person is playing guitar, behind them stands a very bright lamp.
A person is in a band.
Playing guitar doesn't mean you're in a band.
exists e1 p1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & exists e2 s2 x3.(behind(e2,x1) & Actor(e2,x3) & v_stand(e2) & n_lamp(x3) & a_bright(s2) & Theme(s2,x3) & r_very(x3)) & n_thing(x1) & that(x2,p1) & n_guitar(x2) & n_person(x1) & a_young(s1) & Theme(s1,x1))
exists p1 x1.(exists x2.(in(x1,x2) & n_band(x2)) & n_person(x1))