你看到这个单线，如果你视力够好。

And you see here single lines, if you have good eyes.

youdao

千万不要等着有眼部疾病的症状出现的时候再去就医，某些致盲的眼疾在使你视力模糊之前是不会有任何症状的征兆的。

No, it's not okay to wait for symptoms to appear. Some blinding eye diseases have few warning signs before they've taken away your vision.

youdao

当你被动地坐在电视机前的时候，你的肌肉正在变成脂肪，你的脸色正变得苍白，你的视力正在受损。

While you are sitting passively in front of the TV set, your muscles are turning to fat, your complexion is fading, and your eyesight is being ruined.

youdao

If your have good eyesight from the distance that you're at you can see the vessels leading out of the heart and into the lungs, and the lungs are these darker spaces within the ribcage.

如果你的视力足够好的话,你们能看到,由心脏发出血管,进入到肺部,肺是胸腔里这片比较暗的部分

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