说明文段落的理解

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,#,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,#,段落理解,-,说明文,高三复习,Teaching Objectives,通过阅读说明文,段落，,总结并掌握,说明文段落,主旨的概括方法,；,理清段落信息之间的逻辑关系，画出段落结构图；,Hollywoods theory that machines with evil(,邪恶,)minds will drive armies of killer robots is just silly.The real problem relates to the possibility that artificial intelligence(AI)may become extremely good at achieving something other than what we really want.In 1960 a well-known mathematician Norbert Wiener,who founded the field of cybernetics,（控制论）,put it this way:“If we use,to achieve our purposes,a mechanical agency with whose operation we cannot effectively interfere(,干预,),we had better be quite sure that the purpose which we really desire.”,Lead in,阅读下面文,段，简单说出说明文,的语篇特点。,说明文主要是对,事物或事理,进行客观说明的一种,文体。,说明文,结构句式复杂,，专业术语多,，抽象,度,高,。但同时说明文,中心鲜明突出,、文章,逻辑性,和,条理性,比较强。因此,要,掌握,说明文,的说明,方法,、以积极，冷静,的心态面对。,How to get the main idea of a paragraph in expository texts?,Activity 1:,阅读,下列,3,个段落,并,1,）找出段落的核心句；,2,）归纳核心句可能出现的位置；,3,）归纳核心句的语言特点,。,Researchers in Spain and England recently found that the worms of,the greater wax moth,(,大蜡螟,)can break down polyethylene,which accounts for 40%of plastics.The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours,and the worms consumed and broke down about 92 milligrams,or almost 3%of it.To confirm that the worms chewing alone was not responsible for the polyethylene breakdown,the,researchers made some worms into paste(,糊状物,)and applied it to plastic films.14 hours later the films had lost 13%of their mass-apparently broken down by enzymes(,酶,)from the worms stomachs.Their findings were published in Current Biology in 2017.,Researchers in Spain and England recently found that the worms of,the greater wax moth,(,大蜡螟,)can break down polyethylene,which accounts for 40%of plastics.,段首,Measles(麻疹),which once killed 450 children each year and disabled even more,was nearly wiped out in the United States 14 years ago by the universal use of the MMR vaccine(疫苗).But the disease is making a comeback,caused by a growing anti-vaccine movement and misinformation that is spreading quickly.Already this year,115 measles cases have been reported in the USA,compared with 189 for all of last year.,段中,MMR vaccine(疫苗).,But the disease is making a comeback,caused by a growing anti-vaccine movement and misinformation that is spreading quickly.,Why would human beings waste a third of their lives sleeping when they could be doing more important things like looking after their families or working?Some scientists believe sleeping helps recharge the body,while others think it is important for strengthening newly-formed memories.Now,there is new evidence which suggests that the purpose of sleep may be to forget some of the millions of new things we learn each day.,formed memories.,Now,there is new evidence which suggests that the purpose of sleep may be to forget some of the millions of new things we learn each day.,段尾,The,neurons,(,神经元,)in the human brain consist of fibers called,dendrites,(,树突,).These grow as we learn new things and connect the brains cells to each other at the contact points called,synapses,(,突触,).The larger the dendrites become and the more cells they connect,the more information we store.,What is this paragraph mainly about?,How neurons grow,Memory storage in neurons.,Structures of the human brain,How brain cells connect to each other.,在一些文段中，没有可以概括全段意义的主题句，必须根据文中所提供的事实细节，进行,全面分析,，然后归纳成一般概念。,语篇的组织遵循特别的约定（,Van Dijk,1977,）。作为语篇的基本组织单位之一，段落组织也遵循相应的约定，作者在组织段落时，,一个段落只表达一个观点,。为了实现这个目标，段落中的每个句子都相互衔接并力争服务于段落主旨意思的表达。,How to get,clear about the logical relationships,（逻辑关系）,within a paragraph,?,Activity 2:,阅读,下面的段落,1,）给段落分层并归纳层意；,2,）画出本段的结构图；,Life,in the Clear,Transparent,animals let light pass through their bodies the same way light passes through a window,.,Light typically travels in a straight line.But some materials slow and scatter(,散射,)light.Others absorb light,stopping it dead in its tracks.,But,a transparent object doesnt absorb or scatter light.Light can pass through it without bending or stopping,.,Animals are built of many different materials-skin,fat,and more-and light moves through each at a different speed.Every time light moves into a material with a new speed,it bends and,scatters,(,散射,),.,Transparent animals use different tricks to fight,scattering.Some,animals are simply very small or extremely flat.Without much tissue to scatter light,it is easier to be,see,-,through,.Others build a large,clear mass of non-living jelly-lie(果冻状的)material and spread themselves over it.,射,),.,Transparent,animals use different tricks to fight,scattering,Animals built of different materials make light bend and scatter.,Transparent,animals,use different tricks to fight,scattering.,Some animals.,Others,e,xamples/explanation,contrast,Example of a structure map,Finish the exercises on the handout.,B,e,positive and active,说明文阅读考察的是阅读能力、逻辑思维能力，而不是要求考生全面、系统、透彻弄懂相关的知识。基于此，我们在做说明文试题时,，保持冷静的头脑，积极去应对遇到的困难。,Confidence