A man is standing behind a giant green machine.
A woman sits atop a red tractor.
A man and a woman are different genders and you cannot be both at the same time.
exists e1 s1 s2 x1 x2.(behind(e1,x2) & n_machine(x2) & a_green(s2) & Theme(s2,x2) & a_giant(s1) & Theme(s1,x2) & Actor(e1,x1) & v_stand(e1) & n_man(x1))
exists e1 s1 x1 x2.(atop(e1,x2) & n_tractor(x2) & a_red(s1) & Theme(s1,x2) & Actor(e1,x1) & v_sit(e1) & n_woman(x1))