Men in the park.
Some men are in a backyard cooking food on a grill.
Men in a backyard can not be in the park.
exists x1 x2.(n_park(x2) & a_topic(x1) & in(x1,x2) & n_man(x1))
exists p1 x1.(exists x2 x3 x4 x5.(in(x1,x2) & on(x2,x5) & n_grill(x5) & n_food(x2) & of(x2,x4) & n_cooking(x4) & of(x2,x3) & n_backyard(x3)) & n_man(x1))