Invest in smaller bottles and use the bathroom supplies, such as shampoo, soap, mouthwash, etc., provided by the hotel to keep your toiletry case light.

购买小瓶包装的，并尽量使用旅馆提供的盥洗用品：像洗发水、肥皂、漱口水、吹风机等，来让你的洗漱包轻便。

youdao

In a further effort to spread the safe sex message, hotel guests in Papua New Guinea will soon find complimentary condoms alongside the free soap and shampoo in their rooms.

VOA: standard.2009.04.04

Derreck Kayongo's Global Soap Project collects partially used hotel soap and reprocesses it to save lives.

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The Global Soap Project recycles uses bars of soap from hotel rooms and distributes them throughout the world.

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For instance Best Western, Carlson, Mandarin Oriental and others have teamed up with Clean the World, an initiative that recycles your partially used soap from the hotel room.

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