原文：Weshouldremembertwothingsaboutthisenergysource.First,theworld’spresentandprecariousdependenceonfossilfuels—firstcoal,andthenoil—isonlyabouttwohundredyearsold.Beforethat,mostoftheenergyrequiredbyhumanbeingsforheating,cookingandindustrialpurposewassuppliedfrombiologicalsources.Bythis,wemeanmainlywood,oritsderivative,charcoal.题目：Theuseofcharcoalforcookinghasbeenacommonpracticeforhundredsofyears.
