a fifth wheel

常見例句

雙語例句

• A car does not need a fifth wheel.
  一輛車通常不需要第五衹輪子。
• By definition, a fifth wheel is a wheel or a portion of a wheel with two parts rotating on each other that sits on the front axle of a carriage and adds extra support so it doesn’t tip.
  通過定義，第五個輪子，是成爲(wèi)一個四輪馬車的前車軸上互相鏇轉(zhuǎn)的兩個部分的一個輪子或一個輪子的一部分，而加上一個額外的輔助輪子，這樣它就不會傾斜。
• He was the only one without a date, so he felt like a fifth wheel.
  他是唯一沒被邀請的人，因此他感到自己很是多餘。

權(quán)威例句

• Trailers are typically attached to tractors by a "fifth wheel, " in which a coupling pin on the trailer fits into the center of a large horseshoe-shaped piece of metal.
  NPR: Runaway Trailer Crashes Rare; NY Accident Killed 7
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