Stay up to date with our Up First newsletter, sent every weekday morning.驾驶员开始看到高油价有所缓解。时隔数月，AAA称，汽油每加仑的平均价格首次跌破4美元。
Stay up to date with our Up First newsletter, sent every weekday morning. Drivers are starting to see some relief from high fuel prices. For the first time in months, the average price of a gallon of gasoline has dipped below $4, according to AAA.
该价格于周二跌破4美元关口，目前全国平均价为每加仑3.94美元的常规汽油。过去一个月油价下跌了约40美分，其中大部分跌幅发生在过去两周内。
The price crossed below the $4 threshold on Tuesday, and is currently down to a national average of $3.94 for a gallon of regular. Prices have dipped about 40 cents over the past month, with much of that decline happening in the past two weeks.
“很多人会认为选举与此有关，但这纯属谣言，”GasBuddy煤油分析负责人帕特里克·德哈恩在其行业通讯中写道。
"Many will assume the election had something to do with it, but that's a myth," Patrick De Haan, head of petroleum analysis at GasBuddy, wrote in his industry newsletter.
他补充说，汽油价格下跌的原因更为平常：目前“季节性转变而非政治推动了加油站的缓解。”秋季汽油价格通常会下降。
Instead, he continued, gasoline prices are dropping for a more banal reason: "For now, it's the seasonal shift, not politics, driving the relief at the pump." Gas prices often ease in the fall.
其一原因是：夏季已结束，夏季是加油的高峰期。（AAA指出，寒冷天气下驾车人数减少。）需求减少，市场上有更多汽油。加油厂也在秋末完成年度维护。因此，汽油供应增加。市场上出售的汽油混合物成本更低。
One reason: It's no longer summer, which is the peak season for gas. (Fewer people drive in colder weather, AAA points out.) With less demand, there's a touch more gas on the market. Refineries also finish their annual maintenance by late fall. So that adds a bit more gas to go around. And the blend of gasoline that's on the market gets cheaper.
加油厂每年会生产两种汽油：夏季调和汽油和冬季调和汽油。夏季调和汽油因在高温下挥发较慢而产生更少烟雾；冬季调和汽油有助于发动机在严寒中启动，并使用少量但烷，从而降低成本。
Refineries make two types of gasoline every year: summer and winter blends. The summer blend produces less smog, because it evaporates less quickly in the heat; the winter blend helps engines start up in freezing weather, and uses a bit more butane, which helps lower its cost.
但Rystad Energy地缘政治负责人何尔希表示，这些都不是导致汽油价格下跌的最大原因。主要推手是布伦特原油价格下跌，目前报价约为每桶90美元，而炼油厂需要它来生产汽油、柴油和航空燃油。
But none of those are the biggest reason why gas prices are falling, says Jorge León, head of geopolitics at the research group Rystad Energy. The main driver is the falling price of Brent crude oil, which is now down to about $90 a barrel, and which is what refineries need to make gasoline, diesel and jet fuel.
该价格下降是因为中东通过管道输出的原油有所增加，同时市场交易员对美伊外交努力加强的欢欣鼓舞也推动了这一下降。
That price is falling because there's a bit more oil coming out of the Middle East via pipelines, and because market traders have rejoiced at the intensifying diplomatic efforts between the U.S. and Iran.
如果战争升级，这一进展可能会轻易被逆转，Leon在给NPR的电子邮件中写道。“特朗普总统可能会将进一步的军事行动视为在1月民主党控制国会之前争取谈判筹码的手段。如果出现新的升级，上周原油价格的下跌可能会迅速回升，”他写道。对于汽油价格同样适用此情况。
That progress could easily be reversed if the war escalates, León wrote in an email to NPR. "President Trump may see further military action as a way to regain negotiating leverage before Democrats take control of Congress in January. If we see renewed escalation, much of last week's oil price decline could quickly reverse," he wrote. The same would be true for gas prices.
国会民主党表示支持结束伊朗的战争。虽然他们在直接行动上权力有限，但他们掌握着公共资金的分配权，可以拒绝拨付额外的战争经费，或阻止关键官员的确认。
Congressional Democrats have expressed their support for ending the war in Iran. While they have limited power to do that, they do control the power of the purse, and can withhold additional war funding or hold back confirmations of key officials.
目前，如果布伦特原油价格持续下跌，加油站的价格也可能随之下降。“然而，这并不意味着完全‘正常化’，即回到冲突开始前的价格水平，”道琼斯能源公司炼油与油品市场执行主管Jaime Brito在给NPR的电子邮件中写道。
For now, if the price of Brent crude keeps falling, so could prices at the pump. "However, this does not mean a complete 'normalization,' a return to the price levels we had before this conflict started," Jaime Brito, executive director of refining and oil markets for Dow Jones Energy, wrote in an email to NPR.
要恢复战前的汽油价格，整个石油供应链必须恢复。那些为避开霍尔木兹海峡而长期绕行的船只需要返回出发地，然后恢复正常航线，将原油运往炼油厂。这些炼油厂需要生产足够的燃料以缓解全球需求 — — 同时消化库存的流失。整个过程在持久和平协议达成后可能需要数月时间。
To get back to pre-Iran war gas prices, the whole oil supply chain would have to recover. Ships that have been running long alternative routes to avoid the Strait of Hormuz would have to return to their points of origin, then resume their normal routes, taking crude oil to refineries. Those refineries would have to pump out enough fuel to alleviate global demand — and depleted stockpiles. The whole process could take months after a lasting peace deal.
“恢复到这些价格水平需要整个全球供应链的原油产量、运输和炼制恢复正常，”Brito继续说道。
"Coming back to those levels will require a return to normal crude production, shipping and refining of the entire global supply chain," Brito continued.
尽管每加仑4美元现在可能看起来很便宜，但根据其网站的更新，美国汽油价格仍是该时段历史最高水平。
And while $4 a gallon may seem like a bargain these days, in an update on its website, AAA said that gasoline prices are still the highest they've ever been at this time of year.