A man in a white shirt and hat playing a guitar.
A man restrings his guitar.
A man cannot be playing a guitar while he restrings a guitar.
exists e1 s1 x1 x2 x3 x4 x5 x6.(a_topic(x1) & Theme(e1,x6) & Actor(e1,x5) & v_play(e1) & n_guitar(x6) & (x1 = x5) & in(x1,x2) & n_hat(x4) & n_shirt(x3) & a_white(s1) & Theme(s1,x3) & subset_of(x4,x2) & subset_of(x3,x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_restring(e1) & n_guitar(x2) & of(x2,x1) & n_male(x1) & n_man(x1))