知识扩展
词组短语 flex fatigue挠曲疲劳；

中文词源： flex 屈伸 来自flexible的回构词。 flex
精选例句

常见考点例句：

As you slowly return to the starting position , turn your palms toward the ceiling , flex your arms and curl the dumbbells in toward your shoulders .

当慢慢回到原位置时，手掌朝上，弯曲手臂，朝肩部方向运动哑铃。

Scientists have long speculated that ocean waves could cause an ice shelf to flex and break , but this is the first time researchers have observed a tsunami having this effect .

长期以来，科学家们推测海浪是可以引起冰架的收缩和瓦解的，但这是研究者们第一次观测到海啸拥有着这样的效果。

When a knife cuts your skin , it leaves a relatively clean cut compared to paper , which will flex a little and do more microscopic damage to the skin .

当皮肤被小刀划破时，伤口相对平整光滑；被纸片割伤就不同了，此时的伤口呈略微弯曲状，对皮肤的微创也会更多一些。

During yawning , the walls of the maxillary sinuses ( located in the cheeks on each side of the nose ) flex like bellows and help with brain cooling , according to the researchers .

这两位研究人员表示，在打哈欠时，上颌窦的壁部（位于鼻子两边的脸颊上）像风箱一样弯曲，帮助大脑降温。

The severing at these points causes nerve damage that makes the wrist flex and the fingers curl up in the manner of a waiter taking a backhanded tip .

这些在这几个点上的切割造成神经损伤以至于是手腕弯曲手指卷起就像是服务员拿背后的小费这个动作。