Children sleeping on the floor.
Some friends are having a sleepover.
A sleepover consists of a party, children sleeping on the floor does not.
exists e1 x1 x2.(n_floor(x2) & ne_nam_children(x1) & on(e1,x2) & Actor(e1,x1) & v_sleep(e1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & n_sleepover(x2) & n_friend(x1))