Only if the red light comes on is there any danger to employees.

只有红灯闪亮时才有危及职工的险情。

《牛津词典》

The light turns red.

灯变红了。

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The plant on top would absorb most of the red light for photosynthesis, but reflect most of the far-red light.

顶部的植物会吸收大部分的红光进行光合作用，但反射大部分的远红光。

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As the taxi stopped for a red light Paul noticed a flower shop.

VOA: special.2009.04.11

So this last version of the red light introduces interesting complications which I don't think should confuse us.

所以，关于红灯的这最后一个例子,让我们思考了平时不会思考的问题。

耶鲁公开课 - 文学理论导论课程节选

It's sorting things based on the light frequencies, but it doesn't have the experience of seeing red.

它只是根据光频来分辨颜色而已,并没有看见红色的体验

耶鲁公开课 - 死亡课程节选

The surface of these planets would be quite different, due to the light from the red dwarf.

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Hamilton said he had been told by the team that the red light was on at the end of the pit lane, but that the warning came "a little bit late".

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It looks like Bucchere entered the intersection just as the light turned red.

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