广博吧相关coal的学习知识
学习coal知识内容，就在coal专题，精彩的coal相关知识，品味coal相关内容，分享coal相关精彩要点，统统都在coal专题，通过coal专题的学习，会让你对coal知识有了精细化了解，让您在学习中没有问题。
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Save half of the coal
Asmarthousewifewastoldthattherewasakindofstovewhichwouldonlyconsumehalfofthecoalshewasburning.Shewasveryexcited,andsaid:"That'llbeterrific!Sinceonestovecansavehalfofthecoal,ifIbuytwo,nocoalwillben...