That is why it is much easier to float when we are completely under the surface, head and all, than if we try to keep our heads out. (4)

这是我们将头和全身完全钻进水中进行漂浮，比我们试图把头保持在水面上作漂浮，要容易得多的原因。

youdao

The reason you have to get it out of your head is you need to be able to see it on a surface that is not in your mind.

这么做的原因是,你需要,客观地观察它,而不是看它在你大脑中的样子。

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He knelt down and crawled from the switch rails to the frog of the crossover, sliding his hand along the running surface and the head of the rail and feeling for possible corrugations or dents, or burrs shaved off by the wheels of the locomotives.

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Heck, even the Surface Pro reared its head backstage at the show.

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Prosecutors charged Woodward with first-degree murder, accusing her of shaking Matthew and slamming his head against a hard surface.

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