“put option”中的long指的并不是期权到期前的长度，而是指交易者买入期权，希望能在之后以较高价格卖出的行为。“put option”买入看跌期权，指购买者支付权利金，获得以特定价格向期权出售者卖出一定数量的某种特定商品的权利。看跌期权买入者往往预期市场价格将下跌。A long put refers to buying a put option, typically in anticipation of a decline in the underlying asset. The term "long" here has nothing to do with the length of time before expiration, but rather refers to the trader's action of having bought the option with the hope of selling it at a higher price at a later point in time. A trader could buy a put for speculative reasons, betting that the underlying asset will fall which increases the value of the long put option. A long put could also be used to hedge a long position in the underlying asset. If the underlying asset falls, the put option increases in value helping to offset the loss in the underlying.

交易者可以买入与自己即将卖出或已经购买的期货合约相关的看跌期权，一旦商品价格下降，可以履行看跌期权，以较高的执行价格卖出期货合约，然后按下跌的价位低价买入期货合约平仓获利，在弥补所支付的权利金后还有盈余，这部分盈余可以弥补因价格下跌低价出售商品所带来的亏损；或者直接将期权高价卖出，获得权利金收益，这均可起到保值的作用。如果商品价格没有下降而是上涨了，交易者可以放弃履行期权，权利金的损失可以由高价出售商品或资产的收益所弥补。与直接在期货市场卖出期货合约进行套期保值相比，这种交易方式风险小、交易灵活。

与“long put”相对应的是“short put”卖出看跌期权卖出看跌期权是指卖出者获得权利金，若买入看跌期权者执行合约，卖出方必须以特定价格向期权买入方买入一定数量的某种特定商品。当投资者预期某种特定商品市场价格上涨时，他往往卖出看跌期权。A short put refers to when a trader opens an options trade by selling or writing a put option. The trader who buys the put option is long that option, and the trader who wrote that option is short. The writer (short) of the put option receives the premium (option cost), and the profit on the trade is limited to that premium.

如果交易者预计相关商品或资产的价格会出现小幅上涨，并预计不会出现大幅下跌时，通过卖出看跌期权可以获得权利金收益，可以避免现货商品或资产价格上涨的风险，从而起到保值的作用。不过在利用卖出看跌期权套保时需要注意，即使预测正确，期权交易带来的收益也是有限的，最高仅为权利金；但是如果预测错误。商品或资产价格大幅度下跌，期货价格跌至看跌期权的执行价格以下时，套保者可能会面临期权买方要求履约的风险，期权交易会带来较大的损失，这会抵消价格下跌给现货市场带来的收益，不能取得保值效果。因而在利用卖出看跌期权进行保值操作时，需要慎之又慎。

以下为相关双语示例，供参考：

When you sell a put option, you are said to be short the put. A trader, when shorting a put option, sells the right to sell short the option’s underlying stock at a later date – any time before the option’s expiration – at the price outlined in the option contract (known as the strike price).

当你出售看跌期权时，即被视为卖出看跌期权。交易者在卖出看跌期权时，出售的是以期权合同中所述的价格（即执行价格）在期权截止期间的任何时候卖出期权相关股份的权利。

A long put could also be used to hedge a long position in the underlying asset. If the underlying asset falls, the put option increases in value helping to offset the loss in the underlying.

买入看跌期权常常也会被用于对冲相关资产中的长仓。若相关资产价格下跌，看跌期权可帮助弥补相关资产的损失。