The man without a shirt is sitting on a rock by a tree.
The male model posed on the rock.
the man without a shirt was a model who posed on a rock
exists e1 x1 x2 x3.(n_man(x1) & by(e1,x3) & n_tree(x3) & on(e1,x2) & n_rock(x2) & Actor(e1,x1) & v_sit(e1) & -exists x4.(with(x1,x4) & n_shirt(x4)))
exists e1 s1 x1 x2.(n_rock(x2) & n_model(x1) & a_male(s1) & Theme(s1,x1) & on(e1,x2) & Actor(e1,x1) & v_pose(e1))