Screeners:Excuse me ,Is this your bag? Passenger: Yes. Screeners: What’s that? Passenger: It is a screwdriver. Screeners: It is forbidden to take it on board. Passenger :Oh. Sorry. I don’t know the regulations. What should I do? Screeners: We could keep it for you. But you must come back in one month. Or you can give it up. Passenger :I’ll give it up. Screeners: Thank you for your corporation.