Man shows his skills on waterskis.
Sad man shows his skills on waterskis.
Not all men are necessarily be sad men.
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_show(e1) & on(x2,x3) & n_waterski(x3) & n_skill(x2) & of(x2,x1) & n_male(x1) & n_man(x1))
exists e1 x1 x2 x3 x4.(Theme(e1,x3) & Actor(e1,x1) & v_show(e1) & on(x3,x4) & n_waterski(x4) & n_skill(x3) & of(x3,x1) & n_male(x1) & n_man(x1) & (x1 = x2) & ne_nam_sad(x2))