1. Foreign exchange has the following forms: 1. Foreign currency, including banknotes and coins; 2. Foreign currency securities, including government bonds, government bonds, corporate bonds, stocks, coupons, etc. ; 3. Foreign currency payment vouchers, including bills, bank deposit vouchers and postal savings vouchers; 4. Other foreign exchange funds. There are many sources of foreign exchange, including investment and international trade settlement. Therefore, the understanding of the first sentence is one-sided, and the increase in foreign currency may be trade income or foreign deposits, rather than the exchange of RMB into foreign currency. The second sentence is the same.

The third sentence is that demand remains unchanged and supply increases, indicating that supply exceeds demand, which should be the first case; On the contrary, the fourth sentence is aimed at the second situation.