- fifth wheel
 - 第五个轮子;备用轮;多余的人
 
参考例子
           - 1.Since my girlfriend didn't come, I was a fifth wheel at the party.
 - 因为我女友没有来,我在舞会上成为多余之人。
 
- 2.All the boys and girls were dancing at the party while I sat at a table alone, feeling like a fifth wheel.
 - 晚会上,所有的男孩和女孩都在跳舞,只有我孤零零地坐在桌边,感觉自己仿佛是一个多余的人。
 
- 3.My son asked me to come help at his school track meet but I felt like a fifth wheel when I got there: they already had enough people to help so I just stood there feeling useless.
 - 这位家长说:我的儿子要我在他学校开运动会的时候去帮忙。可是,我到了那里觉得自己似乎是多余的,因为他们已经有好多人在帮忙,我只好站在那里没事干。
 
英文解释
           - n.
 - 1.someone or something that is unwanted and unneeded
 - 2.an extra car wheel and tire for a four-wheel vehicle
 - 3.a steering bearing that enables the front axle of a horse-drawn wagon to rotate
 
网络释义
               - fifth wheel
 - 第五轮; 多余人; 连接轮; 联结轮;
 
- Fifth-wheel
 - 多余的人或物; 联接器;
 
- A Fifth-wheel
 - 没用的人;
 
- fifth-wheel tester
 - 五轮仪;
 
- fifth wheel method
 - 第五轮仪; 五轮仪法; 第五轮仪?; 光电屏障;