- 问题详情:Organicfarmersalsousemanyothermethodstoproducerichsoil.Theyoftenchangethekindofcropgrownineachfieldeveryyear.Forinstance,theymaygrowcornorwheatinafieldoneyear,andthengrowbeanstherethenext.Whydifferentcropsaregrownisbecausetheyputimportantmine...
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