You'll need to show them when you claim your travelling bags on your arrival in Hangzhou. And these are your boarding cards. You'll need to show them at the departure gate. L:Can we board the plane now? C:Please wait in the departure lounge until boarding is announced. L:The flight is now boarding at Gate Two. Let's go and board it. Fasten your seat belts before the plane takes off. After the plane arrives in Hangzhou, please don't leave the airport until we get all the checked luggage.