This showed conclusively that the increase in plantsubstance could not have come from the soil alone.
这表明：植物物质的增加不可能单单来源于土壤。
2
Petrifaction may also involve a simultaneous exchange of the original substance of a dead plant or animal with mineral matter of a different composition.
石化还可能同时涉及将死亡的动植物的原有物质与不同成分的矿物质进行交换的作用。
3
WHO recommends combinations that contain derivatives of artemisinin — a substance extracted from the plant Artemisia annua — along with another effective antimalarial drug.