She whirled suddenly, one arm reaching for something near her side but failed, and it made her stumble.

她突然转动身子，一只胳膊伸向身边，似乎想抓住什么但没抓到，这让她绊了一跤。

youdao

He raised one arm and then the other.

他先举起一只手，然后举起另一只。

《牛津词典》

Other children around always wondered how he could play basketball with just one arm.

周围的其他孩子一直都想知道他是怎么做到用一只胳膊打篮球的。

youdao

"On station one,we have robot arms. And what happens is the robots have different joints like a human arm -- one at the shoulder,one at the elbow, wrist and then a claw.

VOA: special.2010.07.28

Store employee Brian McLelland snaps the arm off one faceless figure and rearranges its black t-shirt.

VOA: standard.2010.02.17

To warm up, she'll do balance-based exercises including a one-arm, one-leg plank to strengthen her core.

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His father, Mangelal Singh, also insists that Ram Singh would not have been able to orchestrate a suicide because he only had the effective use of one arm- Ram Singh had damaged his right arm in a driving accident in 2009.

BBC: Profile: Delhi rape accused Ram Singh

Turns out I was the only person in our group -- including one guy who had only one good arm -- who didn't complete the ride.

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