A man is playing an acoustic guitar.
A man is entertaining an audience by playing guitar.
Not all man playing an acoustic guitar is entertaining an audience.
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 e2 x1 x2 x3.(by(e1,e2) & Theme(e2,x3) & Actor(e2,x1) & v_play(e2) & n_guitar(x3) & Theme(e1,x2) & Actor(e1,x1) & v_entertain(e1) & n_audience(x2) & n_man(x1))