当胳膊在头顶部时，一定要保证你的身体的流线型和后仰的弓形，这样才能保证你的手先入水。

Once your arms are over your head, be sure to streamline and arch your body so that your hands hit the water first.

youdao

他先举起一只手，然后举起另一只。

He raised one arm and then the other.

《牛津词典》

然而，约翰先举起了手。

John, however, had held up his hand first.

youdao

Leave your hands up so that Jude can catch that, so people can see at home, okay.

先不要放下手,让裘德拍一下,这样看视频的人也能看到

耶鲁公开课 - 博弈论课程节选

So once again, no abstentions this time: who would choose Alpha? Let's have a show of hands again, keep your hands up a second.

这次也不允许弃权,谁会选择α,请举下手,先别放下手

耶鲁公开课 - 博弈论课程节选

What you'll notice is this hit and this hand went back up.

你们会看到,先有撞击,然后手会回到原先的高度

耶鲁公开课 - 心理学导论课程节选