FourGreatInventions四大發明學習目標1.了解古代的四大發明2.體會四大發明帶給世界的影響第一部分了解古代四大發明PartOne:UnderstandingthefourGreatinventionsofancienttimesTheinventionofmovable-typeprintingisagreattechnologicalrevolutioninthehistoryofprinting.Themethodofmovabletypeprintingistomaketheyang-weninversemodelofasinglecharacter,thenselectthesinglecharacteraccordingtothemanuscript,arrangeitinthefontplate,inkprinting,andthenremovethemodelafterprinting,andleaveittobeusedagaininthenextprinting.活字印刷術的發明是印刷史上一次偉大的技術革命。活字印刷的方法是先制成單字的陽文反文字模，然后按照稿件把單字挑選出來，排列在字盤內，涂墨印刷，印完后再將字模拆出，留待下次排印時再次使用。活字印刷術司南PapermakingisoneofthefourgreatinventionsofChina.IntheWesternHanDynasty,peoplealreadyknewthebasicmethodofmakingpaper.IntheEasternHanDynasty,theeunuchCAILunsummeduptheexperienceofhispredecessors,improvedthepapermakingprocess,andusedplantfiberssuchasbark,hemphead,ragsandoldfishnetasrawmaterialstomakepaper.Thequalityofpaperwasgreatlyimproved.Thispapermaterialiseasytofind,cheapandeasytopromote.Sincethen,theuseofpaperhasbecomemoreandmorecommon.Papergraduallyreplacedsilkandbecameawidelyusedwritingmaterial,whichalsofacilitatedthecirculationofclassicalbooks.造紙術，是中國四大發明之一。西漢時期，人們已經懂得了造紙的基本方法。東漢時，宦官蔡倫總結前人經驗，改進造紙工藝，用樹皮、麻頭、破布、舊魚網等植物纖維為原料造紙，紙的質量大大提高。這種紙原料易找，價格便宜，易于推廣。此后紙的使用日益普遍，紙逐漸取代簡帛，成為人們廣泛使用的書寫材料，也便利了典籍的流傳。火藥，又被稱為黑火藥，由硝酸鉀、木炭和硫磺機械混合而成。是在適當的外界能量作用下，自身能進行迅速而有規律的燃燒，同時生成大量高溫燃氣的物質。Gunpowder,alsoknownasblackpowder,isamechanicalmixtureofpotassiumnitrate,charcoal,andsulfur.Undertheactionofappropriateexternalenergy,itcancarryoutrapidandregularcombustionandgeneratealargenumberofhigh-tempe