They are a shade of red bordering on brown.

它们呈暗红色，近乎棕色。

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Her nails were varnished a brilliant shade of red.

她的指甲上涂了一层鲜亮的红指甲油。

《牛津词典》

Some biologists hypothesize that a plant will stop growing if it's in the shade of another plant, a reaction that's triggered when it senses an unusual ratio of red light to far-red light.

一些生物学家假设，如果一株植物处在另一株植物的荫蔽下，它就会停止生长，当它感知到红光与远红光的不寻常比例时，反应就会触发。

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The phytochrome can then be exposed to a different shade of red light to turn the gene off.

FORBES: Cyborg Yeast Have Their Genes Controlled By Computer

He is from a different shade of red than the standard communist cadre.

CNN: Red star

This may cloak the government in a paler shade of red.

ECONOMIST: After Sonia, Singh steps in | The