free of
这个偏远岛屿的水天然没有工业污染物。
The remote island's water is naturally ___free ___of industrial contaminants.
有机农民通过自然方式保持土壤肥沃且无病害。
Organic farmers keep their soil rich and ___free ___of disease through natural means.
自然方法使空气、土壤、水和作物免受化学物质污染。
Natural methods keep the air, soil, water, and crops ___free ___of chemicals.