Shorting means that the price will fall. We can understand it this way: when the exchange rate is high, we think it may fall in the future. At this time, we borrow money from the exchange and sell it first when the exchange rate is high. When the exchange rate falls, we will buy back the sold currency and return it to the exchange. This kind of trading behavior of obtaining the difference by selling high and buying low is called empty, which is a kind of trading that sells first and then buys.

Doing more is the opposite.