flexing

基本解释

She had to concentrate on flexing her pectoral muscle, or the triceps, to power the arm.
为了给手臂提供力量，她不得不用力伸缩她的胸肌或者三头肌。
In itself, this was just an example of the Big Unfriendly Giant flexing its muscles, but it could be a harbinger of things to come.
例子本身只是说明这位不友善的巨人是如何展示他的肌肉的，但它也许可以被看作一个预兆。
The British man has a robotic arm, which he controls by flexing muscles in his shoulders.
这名英国人有支机械手臂，他通过收缩肩膀的肌肉来控制这支手臂。

The Taliban was founded outside the city in 1994, and have recently been flexing their muscles again.

Hezbollah has tightened its grip on southern Lebanon, and is flexing its muscles in Beirut.
NPR: Transcript: Obama's Speech at AIPAC
China has complained loudly about America's recent muscle-flexing, particularly its joint military exercises with South Korea.
ECONOMIST: What lies behind the Dear Leader’s latest trip to China?
And now the group is flexing its muscle in politics and especially in the courts.
NPR: Conservative Christianity and America's Culture Wars

If you flex your muscles or parts of your body, you bend, move, or stretch them for a short time in order to exercise them.
A flex is an electric cable containing two or more wires that is connected to an electrical appliance.
to flex your muscles&rarrsee muscle