1. Luggage Under normal circumstances, each person can check two pieces of luggage. The purpose of making regulations on passengers' luggage is to ensure that your luggage will not occupy special space, so as not to affect other passengers. Each piece of luggage shall not exceed 23kg, and the sum of its length, width and height shall not exceed157cm. Be sure to pay attention to items that cannot be transported as checked baggage! Such articles include: jewelry, precious metals and their products, fragile and vulnerable articles, lame articles, negotiable securities, currency, bills of exchange, antique calligraphy and painting, travel documents, important documents and materials, valuables, etc. 2. Time. Take an international flight as soon as possible! It is strongly recommended that you arrive at the airport three hours in advance when you take an international flight, so as to leave the necessary time for emergencies. 3. Entry and exit documents Foreigners entering the territory of country A must hold valid passports and certificates and complete the entry visa for China; China people enter the country with valid passports and certificates. When Chinese and foreign passengers enter the country, they must submit the completed entry and exit registration card together with their passports, certificates and visas to the frontier inspection station for inspection. During the voyage, the flight attendants will issue entry registration forms or customs declarations, which should be filled in early. All the items that need to be filled in are on the passport, but they must be filled in English capital letters. If you don't fill it out, you can ask the accompanying tour guide or flight attendant to fill it out for you. 4. Time difference If the flight direction is the same as the rotation direction of the earth, the night in the east will be shorter and the night in the west will be longer. This kind of time difference is not suitable, so it is common to catch up with the plane in air travel. You have to start studying. If you are airsick, you can ask the waiter for a sedative or open the air conditioning hole to blow.