A janitor keeping the floors clean and shiny enough to see your reflection.
The janitor doesn't clean the floors at all.
The janitor is either keeping the floors clean or he is not, but not both.
exists e1 p1 x1 x2 x3 x4.(n_reflection(x4) & of(x4,x3) & n_person(x3) & n_floor(x3) & a_topic(x1) & exists p2 s1 s2.(r_shiny(s2) & Topic(s2,p2) & Actor(s2,x3) & a_enough(s2) & exists e2.(Theme(e2,x4) & Actor(e2,x3) & v_see(e2)) & Theme(s1,x3) & a_clean(s1)) & Recipient(e1,p1) & Actor(e1,x2) & Topic(e1,x3) & v_keep(e1) & (x1 = x2) & n_janitor(x1))
exists x1 x2.(n_floor(x2) & n_janitor(x1) & -exists e1.(all x3.(n_thing(x3) -> at(e1,x3)) & Theme(e1,x2) & Actor(e1,x1) & v_clean(e1)))