lights
                    - Suddenly, all the lights in her house went _____. [ ]
 - When the traffic lights are red, we _______ stop.
 - I often see lights in that empty house. So you think I ______ report it to the police?
 - All lights______after the students left the classroom.
 - If it is dark,the lights, please.
 - Remember to the lights when you leave your classroom.