A man is playing an acoustic guitar.
A man is playing a musical instrument.
acoustic guitar is a musical instrument
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_guitar(x2) & a_acoustic(s1) & Theme(s1,x2) & n_man(x1))
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_instrument(x2) & a_musical(s1) & Theme(s1,x2) & n_man(x1))