In foreign exchange transactions, it is impossible to make a profit by buying a certain currency alone, because it is not an index for buying and selling currencies. If you are bearish on the dollar, you should find a currency that will appreciate against the dollar. First sell dollars to buy, and then sell money to buy after the dollar falls. Profits from foreign exchange transactions are transferred between different currencies, and finally return to the original target currency. If the investment is more than the initial investment, it is earned, and vice versa.