![煤-Coal]( "煤-Coal")
- coalissocommonlyusedinlifethatweseldomnoticeit.weburncoaleverydaytoheatfoodandwater.thefirstlocomativewasdrivenbyburningcoal.inwinterwefeelaspecialneedforcoal.thecoalgivesusfire,light,heatandwarmth.industrycannotoperatewithoutcml,therefore,maii9calle...
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