1
the vane shows/indicates [direction]
The vane on the roof shows the wind direction.
屋顶上的风向标指示风向。
风向标；风标
先理解核心含义，再看它在真实句子里的用法。
风向标；风标
a weather vane, a device that shows the direction of the wind
The vane on the roof shows the wind direction.
屋顶上的风向标指示风向。
风向标。
A weather vane.
风向标
mechanical device attached to an elevated structure; rotates freely to show the direction of the wind
沿轴径向安装的若干通常较薄、坚硬、扁平或有时弯曲的表面的任何一种,如涡轮机叶片或风车帆,由流体转动或用于转动流体。
Any of several usually relatively thin, rigid, flat, or sometimes curved surfaces radially mounted along an axis, as a blade in a turbine or a sail on a windmill, that is turned by or used to turn a fluid.
尾翼
a fin attached to the tail of an arrow, bomb or missile in order to stabilize or guide it
The farmer looked up at the weather vane on the barn to see which way the wind was blowing.
农夫抬头看着谷仓上的风向标，想看看风往哪个方向吹。
Before the trip, we checked the wind vane at the harbor to decide whether to sail.
出发前，我们查看了港口的风向标，决定是否出海航行。
The museum guide explained that this ancient vane was used by sailors centuries ago.
博物馆讲解员说，这座古老的风向标是几个世纪前水手使用的。
The vane on the roof shows the wind direction.
屋顶上的风向标指示风向。
这里 vane 指机器里转动的叶片。
The vanes in the turbine are made of metal.
涡轮机中的叶片是金属制成的。
这个义项常用于描述羽毛结构。
The vane of a feather is made up of tiny barbs.
羽毛的羽瓣由细小的羽枝构成。
Not this
The weather vain shows the wind direction.
Use this
The weather vane shows the wind direction.
vain 意为“徒劳的、虚荣的”，与 vane 同音但不同义；表示“风向标”必须拼作 vane。
Not this
The turbine has several vane.
Use this
The turbine has several vanes.
vane 是可数名词，复数形式为 vanes；汉语中没有复数变化，因此容易漏掉词尾 -s。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
风向标
The weather vane on the barn pointed north.
谷仓上的风向标指向北方。
涡轮叶片
The turbine vane was damaged by overheating.
涡轮叶片因过热而损坏。
导向叶片；导流叶片
Guide vanes direct the airflow in the engine.
导向叶片引导发动机中的气流。
叶片泵
A vane pump is used in the hydraulic system.
液压系统中使用了叶片泵。
尾部稳定翼；尾翼
The missile's tail vanes stabilize its flight.
导弹的尾翼使其飞行稳定。
像风向标一样反复无常，见风使舵
His opinions are as changeable as a weather vane, so don't rely on his promise.
他的看法像风向标一样反复无常，所以别指望他的承诺。
……的风向标，……的晴雨表
Retail sales are often a weather vane for consumer confidence.
零售额往往是消费者信心的一个风向标。
像风向标一样摇摆不定，随波逐流
He turns like a weather vane in every debate, agreeing with whoever spoke last.
每次辩论他都像风向标一样转来转去，谁最后发言他就同意谁。
Use vane naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
vane 与 vain 同音：风向标随风转，正如爱慕虚荣的人“见风使舵”。
语域：mixed 常见场景：weather observation、wind turbines/engines、ornithology (feather vane) 该词在不同领域含义不同：日常多指“风向标”，在工程、气象等书面语中常指“叶片、尾翼”等部件。整体属于中性词，但多用于较专业的描述；具体含义需根据语境判断。
以上单词均与 vane（/veɪn/）押韵：rain、pain、lane、main、plane、crane。注意 van（/væn/）拼写相似，但发音不同，不押韵。
Dictionary facts from ECDICT, WIKTIONARY.