People are in a grocery store.
People cook out on the grill.
People who are at grocery store can not be at home cooking on a grill at the same time.
exists p1 x1.(exists x2 x3.(in(x1,x2) & n_store(x2) & of(x2,x3) & n_grocery(x3)) & n_people(x1))
exists e1 s1 x1 x2.(n_grill(x2) & a_out(s1) & Manner(e1,s1) & on(e1,x2) & Actor(e1,x1) & v_cook(e1) & n_people(x1))