Natural fabrics like silk and wool are better insulators than synthetics.

丝绸和羊毛之类的纯天然织物比合成纤维更加保暖。

《柯林斯英汉双解大词典》

On a typewriter or a printer, a ribbon of woven material, for example, cotton, natural silk, synthetic yarn.

打字机和打印机上所使用的一种带状编织品，材料为棉花、天然丝、合成纱等。

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The natural silk and keratin make your hair light, anti-detangle, bringing silky shine and texture.

天然丝及角质蛋白，令头发轻盈柔顺不打结，带来丝般的光泽及触感。

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To the function-based repurposing of natural-wonder materials, like silk and cashmere.

WSJ: We Can't Know What the Future Will Bring | Fashion

And understand that even a single wearing (or probably a lot of try-ons with your new sweater) means your natural-fiber clothes (wool, silk, cotton, cashmere, fur including blends) are no longer sterile when it comes to insects.

WSJ: Ask Teri: How to Keep Moths From Eating Sweaters