Loess, a special soil widely distributing in northwest area of China, is often used as road foundation fillingelement and foundation soil during the large-scale highway construction of this area.
The element mercury has been shown to damage the human nervous system. Yet, since 1856, mercury amalgam is "the" filling dentists have used to repair our teeth.
虽然说汞对人体神经系统有害，但1856年以来，汞齐就被用于修补人们的牙齿了。
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The element mercury has been shown to damage the human nervous system. Yet, since 1856, mercury amalgam is “the” filling dentists have used to repair our teeth.