Your eyebrows should be substantial, but not thick, and have a defined arch in the middle.

眉毛要浓密，但不能厚，中间要有明显的弓形。

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"But your skin is not nearly so thick as mine," replied the crocodile.

“但是你的皮肤远没有我的厚。”鳄鱼回答说。

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Leatherbacks do not have blubber, but they do have a reptilian equivalent: thick, oil-saturated skin, with a layer of fibrous, fatty tissue just beneath it.

棱皮龟没有鲸脂，但它们有和爬行类动物相似的结构：厚且含油的皮肤，下面有一层纤维，再下面是脂肪组织。

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The BBC Weather Centre said observations at the time of the crash on Wednesday showed very low but not thick fog.

BBC: The crane in Vauxhall

There are salt layers similar to, but not as thick as, the pre-salt of Brazil.

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In gyms, the practice takes not only strong feet but thick skin.

WSJ: Barefoot Jocks Keep Gym Members on Their Toes