When you are sitting, keep your elbow on the arm rest.

当你坐着的时候，把胳膊肘靠在扶手上。

《柯林斯英汉双解大词典》

Rest your elbow on the inside of your thigh and let the dumbbell hang.

休息一下你的肘部在里面你的大腿，让哑铃挂起。

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If you find yourself at a standstill and left with only a sliver to rest your elbow, wait for the right moment and then really commit.

如果你发现自己的扶手被占的只剩块搁肘的布的话，就等待时机夺回“领地”吧。

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The 24-year-old, who has suffered shoulder and elbow injuries, said he had needed to "rest and recover".

BBC: 'Exhausted' Tait takes long break

The rest left with a 45 mph fastball, a sore elbow, and a conviction that the radar gun must be defective.

FORBES: Think You Can Top 49-Year-Old Jamie Moyer's 78 MPH Fastball? Think Again.