third wheel

基本解释

"I felt like the third wheel, " she said.
"我觉得自己像个电灯泡，"她说。
But when you just want pure speed its stands upright with the third wheel on top, which supposedly helps keep it balanced.
你要是纯粹想体验速度，它可以竖起来，第三只轮子置于顶部，保持车体平衡。
Larry and Jenny asked me to go out for dinner yesterday, but I said no, because I didn’t want to be a third wheel.
赖瑞和詹妮昨天叫我跟他们一起出去吃饭，但是我没去，我可不想当电灯泡。

In the publicity surrounding the new Twilight film, Eclipse, actor Taylor Lautner often looks like the third wheel.
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With John Krasinski, as the eternal third wheel and second fiddle.
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The third view-busting project is the Millennium Ferris Wheel on the south bank of the Thames, but since this would be only temporary—five years has been suggested—it is causing less worry.
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