外汇中的“多”是指买入另一种货币，然后兑换成基础货币。具体来说，当一个人说他在外汇中做多时，意味着他正在购买另一种货币，以期其相对于基础货币升值，从中获利。在外汇市场中，人们做多通常是通过借入另一种货币，然后将其兑换成基础货币来完成的。这个过程涉及汇率的风险，因为当汇率下跌时，做多的人将面临巨大的亏损。

英文对照：

In foreign exchange, "long" refers to the purchase of another currency and its conversion into the base currency. Specifically, when someone says they are long in the foreign exchange market, it means they are purchasing another currency in anticipation of its appreciation against the base currency for profit. In the foreign exchange market, people typically go long by borrowing in another currency and then converting it into the base currency. This process involves exchange rate risk, because when the exchange rate falls, those who are long will face significant losses.