Lack of collagen, hair drying bifurcation, nails easily broken, dark dull.

缺乏胶原蛋白，头发干燥分叉，指甲容易断裂，灰暗无光泽。

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The stamp was a dark, dull blue colour with a heavy black postmark.

这枚邮票是模糊的暗蓝色的，上面盖着一个粗黑色的邮戳。

《柯林斯英汉双解大词典》

Besides the skin tone, what also make us a little dull are the dark circles of the eyes. Temporary solution is to hide them by makeup.

除了肤色外，黑眼圈也会让我看起来比较暗淡，暂时的解决方法也就只能靠化妆来遮盖。

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The pose and the play of the suspended figure against the architecture are already present, but Miss La La is a dark silhouette against a dim background of dull reds and warm browns.

WSJ: A Dizzying Artistic Feat | Edgar Degas | Miss La La at the Cirque Fernando | By Karen Wilkin