1. There is no password for credit cards in the United States, regardless of whether you have set a password in China. In the United States, you swipe your card yourself and then sign on the card swiping device. There is no handwriting comparison, so you must keep your credit card safe, because anyone can swipe your card.

2. The United States supports Visa, Master or AMEX, but not all places support UnionPay.

3. All card purchases are made from a US dollar account. As the amount in the US dollar account decreases, the limit in the RMB account will be reduced accordingly. For example, if you spend 1,000 US dollars, then your account limit will only be 4. Ten thousand RMB or US$4,000.

4. The billing date and repayment date for U.S. dollars are the same as those for RMB, but when you deposit RMB, you need to notify the bank to purchase foreign exchange and convert it into U.S. dollars. This can be done through online banking or at a branch. If If you have U.S. dollars, you can also deposit U.S. dollars directly. The exchange rate is calculated based on the current exchange rate, which means that if the RMB appreciates during this period of more than a month, you will make money.