A man in a green sweater sharping knifes on a sharping stone.
the man sharpens his knife on a turtle
A man is a general statement while the man is allot more specific, also a stone is very different than a turtle.
exists e1 s1 x1 x2 x3 x4 x5 x6.(a_topic(x1) & in(x1,x2) & on(e1,x5) & n_stone(x5) & of(x5,x6) & n_sharping(x6) & Theme(e1,x4) & Actor(e1,x3) & v_sharp(e1) & n_knife(x4) & (x2 = x3) & n_sweater(x2) & a_green(s1) & Theme(s1,x2) & n_man(x1))
exists e1 x1 x2 x3.(n_knife(x2) & of(x2,x1) & n_male(x1) & n_man(x1) & Theme(e1,x2) & Actor(e1,x1) & v_sharpen(e1) & on(x2,x3) & n_turtle(x3))