Bank of China. Foreign exchange is the abbreviation of international exchange. Among them, Chinese banks can exchange the most foreign currencies, such as British pound, Hong Kong dollar, US dollar, Swiss franc, Singapore dollar, Swedish krona, Danish krona, Norwegian krona, Japanese yen and Canadian dollar. The amount is large, the cost is low, and the service is professional, while other banks exchange less foreign currency, the amount is large, the cost is high, and it is not cost-effective. Foreign exchange is a creditor's right that can be used when the balance of payments deficit is held by the monetary management authorities in the form of bank deposits, securities of the Ministry of Finance and long-term and short-term government securities.