I am flying to Denver, USA, with a layover in San Francisco. Can anyone with experience tell me how to go through the security check?

When leaving China, first find the check-in counter for your flight, check in your luggage, and get your boarding pass. Entering the joint inspection hall, you first go through border inspection, show your passport with a visa, and the police will stamp the exit stamp on the passport; then go through customs and inspection and quarantine. If you need to declare, just declare it. If there is no need to declare, go inside and pass the security gate. ---Put all your belongings and metal objects on your body into the small basket, put it on the conveyor belt of the security inspection machine, and walk through the security gate. Inside is the waiting corridor.

During the flight, fill out the I-94 form and customs form (the flight attendant will issue it to the passenger). Generally speaking, in the airline's flight reading magazine, there are translation instructions for these two forms in various texts. Of course, you must fill them out in English.

After arriving at the first airport in the United States (that is, the airport where you enter: San Francisco), follow the people. There is only one way to reach the "Immigration Hall" and queue up at the "Non-Citizen/Non-Green Card Holder" "foreigner / nonresident" (foreigner / nonresident) team (there are three categories of immigration, US citizen, GreenCard holder, non-citizen / non-green card holder foreigner / nonresident) If you don’t know which queue to queue in, ask someone, there must be someone around at this time Chinese people getting off the plane. See the immigration officer, hand over your I-94, show your passport, customs statement, and other materials (if you are studying abroad, you will need to show your I-20), and have your fingerprints taken. The official approves, stamps your passport, and staples the I-94 half-coupon to your passport. This I-94 is very important and must be surrendered when leaving the United States.

Go through customs inspection and hand in the customs report, and they will conduct random inspections. One possibility is that they wave their hands and you go; the other is that you are asked to put your luggage on the conveyor belt of the inspection machine. After the luggage comes and no one is looking for you, you put your luggage on the trolley and go. Right; there is another possibility. After the machine inspection, customs staff will open the bag for inspection, so you have to open the baggage on the spot and let them inspect it. As long as it is not the third situation, generally speaking, it takes 10 minutes. If it is unpacking and inspection, it is difficult to estimate the time.

If you buy a ticket from an airport in China (such as Beijing) to Denver, then you can check in your luggage directly (be careful not to damage or lose the airline label on your luggage. It has the names of the airports your baggage will depart from and end at). Find your airline's conveyor belt and move it up.

Find the Terminal for your next flight. Major international airports in the United States have several Terminals, including 7 in San Francisco. Each Terminal is connected by light rail. Before entering this Terminal, go through security check again. Whether the queue for security check is long depends on whether your time is during the peak period. After entering this terminal, find the gate where you board the plane, then sit and wait. If it takes a long time, there are power sockets at the bottom of the wall in the airport waiting area, 110V, you can turn on the computer.

First check your flight status, airport map, etc. online, which will make it faster. Be sure to check the website of the airline company for your flight directly, and don’t listen to nonsense.