中文：

贴水是指商品期货交易中由于交割月份的价差而引起的商品实际价格与期货合约价格的偏离。简单来说，贴水是指商品期货价格低于现货价格的情况。

在期货市场中，商品的期货价格与现货价格之间存在一定的关联。由于期货合约的交割期通常是在未来几个月或一年以上，因此在交割期到来之前，期货价格必须与现货价格逐渐接近。如果期货价格远高于现货价格，那么投资者可能会选择在现货市场上购买商品并在期货市场上卖出，从而赚取差价。这种情况被称为“贴水”。

在某些特定市场条件下，例如市场供应紧张或需求增加等因素影响下，商品的现货价格可能会高于期货价格，此时就出现了反向贴水。这种现象通常发生在交割期到来之前的一段时间内，因为投资者知道现货市场上的商品供应相对较少，而需求却不断增加。

英文：

The term "premium" refers to the difference in price between the physical commodity and its futures contract, resulting from the price difference at the time of delivery. In other words, it refers to the situation where the price of the commodity futures is lower than the spot price.

In the futures market, there is a certain correlation between the price of commodity futures and spot prices. Due to the fact that the delivery period of futures contracts is usually several months or more than a year in advance, the price of futures contracts must gradually approach the spot price before the delivery date. If the futures price is much higher than the spot price, investors may choose to purchase the commodity on the spot market and sell it on the futures market, thus making a profit. This situation is called "premium".

Under certain market conditions, such as market supply tightness or increased demand, the spot price of commodities may be higher than the futures price, resulting in a reverse premium. This phenomenon usually occurs in the period before the delivery date, as investors know that there is relatively little supply of commodities on the spot market, while demand is increasing.