The administrative rule has been taking affection refering to cases of hiring foreign teachers I expeienced. rule makers are aiming at social safety and order because some foreigners with invalid visas or evne without passports really bring migraine to chinese government. Except those legally hired by chinese employers, some foreigners came to China by themslves or mislead ,trapped by their town fellows. when they found their destination is not the place they dreamed of , unexpected troubles erupted as you can imagine.