A man dressed in black pants, shirt and hat is sitting on an amplifier playing an instrument that looks like a guitar but it has two necks.
The man is practicing back stage.
Just because the man is playing an instrument does not mean he is practicing. Just because the man is sitting on an amplifier does not mean he is back stage.
exists e5 e2 e3 e1 e4 s1 x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11.(Theme(e5,x11) & Actor(e5,x1) & v_have(e5) & n_neck(x11) & card_eq_2(x11) & n_thing(x1) & for(e2,e4) & Theme(e4,x8) & Actor(e4,x1) & v_play(e4) & like(e3,x10) & n_guitar(x10) & Actor(e3,x9) & v_look(e3) & (x8 = x9) & n_instrument(x8) & on(e2,x7) & n_amplifier(x7) & Actor(e2,x1) & v_sit(e2) & in(e1,x3) & rel(x3,x4) & n_hat(x6) & n_shirt(x5) & subset_of(x6,x4) & subset_of(x5,x4) & n_pants(x3) & a_black(s1) & Theme(s1,x3) & Theme(e1,x2) & v_dress(e1) & (x1 = x2) & n_man(x1))
exists e1 s1 x1 x2.(n_man(x1) & a_back(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_practice(e1) & n_stage(x2))