Unit4 Section A 4a-4d 课件 2025-2026学年人教版英语八年级下册

SectionA(4a-4d) The Wonders of Nature Unit 4 Learning Objectives 能够复习并巩固形容词和副词的比较级和最高级的用法,总结和积累用于比较事物的不同语言结构。 能够总结和梳理大数字的表达法,并理解英文数字表达法的特点。 能够掌握有关地理之最及其高度、长度、深度、面积等信息的问句和答语,使用形容词和副词的比较级、最高级和大数字描述自然景观,并对大自然的神奇产生热爱与敬畏。 1. 流经的距离最远 2. 顺便问一下 3. 第二长河 4. ……和……都 5. 不惜任何代价 6. 古代文明 7. 最长的河流 8. 5,464公里长 9. 了解/学习 10. 把某人/物叫做…… 11.某人/物被称为....(被动) 12.......的发展 travel the farthest by the way the second longest river both...and... at all costs ancient civilizations the longest river 5,464 kilometres long learn about (learned/learnt) call sb./sth.+名称 sb./sth. be called... the development of... Grammar Large numbers Write down the correct numbers according to the geography facts. 1. The surface of the Dead Sea is _ metres below sea level. 2. The Yangtze River is about _ kilometres long. 3. The Nile River is _ kilometres long. 4. Mount Qomolangma is _ metres high. 5. The Mariana Trench is about _ metres deep. 6. The Sahara Desert is about _ square kilometres in size. 416 6,300 6,671 8,848.86 11,000 9,000,000 How can we read these numbers? Read the sentences again. Pay attention to the numbers. What is the biggest desert in the world? It is the Sahara Desert. How big is it? It is about 9,000,000 square kilometres in size. Where is the deepest point in the ocean? It is in the Mariana Trench. How deep is it? It is about 11,000 metres deep. Some deep-sea animals are blind, but they can “see” as well as others. Mount Qomolangma is one of the greatest wonders of the world, and it is still growing taller. The Yangtze River travels the farthest in China and is about 6,300 kilometres long. Find the numbers. 2,534, 507, 890. 12 1.从个位向左数,每三位数加一个逗号(先忽略小数点及后面部分) 2. 从右到左 第一个逗号,读作thousand 第二个逗号,读作million 第三个逗号,读作billion 英语中没有一万和十万的表达! 一万:ten thousand 十万:one hundred thousand point thousand million 3. 在hundred后加and,百位数为0,在thousand后加and and and one two 4. point+小数点后数字逐个读 two billion, billion and Grammar Large numbers How can we read large numbers? five hundred and thirty-four million, five hundred and seven thousand, eight hundred and ninety point one two 1 . 大数字的表达和读法 6 eight thousand, eight hundred and forty-eight point eight six metres thirty hundred and sixty-six thousand, five hundred cubic metres four thousand, three hundred and forty square kilometres five thousand, four hundred and sixty-four kilometres 2 . 单位词 8,848.86 m 366,500 m 5,464 km 4,340 km 8,600 mi eight thousand, six hundred miles 米 千米;公里 英里 1 英里 ≈ 1.609 公里 平方千米 立方米 主+ 谓 基数词+单位词+形容词(原级)(long/wide/high/deep等) 基数词+单位词+in+名词 (length/width/height/depth/size等) 01 02 3 . 长、宽、高、深、面积的表达方式 The sea is about 1,000 metres deep. =The sea is about 1,000 metres_. The Sahara Desert is about 9,000,000 square kilometres in size. 【拓展】“ 数词-单位词单数-形容词 ”合成词 作定语 03 This 20-metre-long rope isn’t enough to help climb the mountain. 询问某物的长、宽、高、深、面积的表达方式 How long/wide/high/deep is/are...?=What’s one’s length/width/height/depth? =What’s the length/width/height/depth of...? _is the sea? = What’s the depth of the sea? in depth How deep 8 Grammar Large numbers Write or spell out the numbers. 4b Mount Kilimanjaro is _ (five thousand, eight hundred and ninety-five) metres high. _ (twenty-five thousand, seven hundred and sixty-eight) cubic metres of water pours down Inga Falls each second. The East African Rift Valley is about 4,000 (_) miles long. The Taklimakan Desert has a total area of about 337,000 (_) square kilometres. 5,895 25,768 three hundred and thirty-seven thousand four thousand / kju b k/ adj.立方的 / k l m n d r / 乞力马扎罗山(非洲最高峰) /r ft / / v li/ 东非大裂谷 / t kl m k n/ 塔克拉玛干 What does each number represent? Grammar Large numbers Write or spell out the numbers. 4b Mount Kilimanjaro is _ (five thousand, eight hundred and ninety-five) metres high. _ (twenty-five thousand, seven hundred and sixty-eight) cubic metres of water pours down Inga Falls each second. The East African Rift Valley is about 4,000 (_) miles long. The Taklimakan Desert has a total area of about 337,000 (_) square kilometres. 5,895 25,768 three hundred and thirty-seven thousand four thousand Height Volume Length Size Grammar Positives Comparatives Superlatives Circle the adjectives which compare things. Underline the adverbs which compare actions. Desert Rainforest There are two amazing places on earth. The first place is much drier than most other places. It is one of the hottest places during the daytime. The days there are usually sunnier than in most places, but the nights can be colder than you think. Plants are not as common as in other places because water is one of the most difficult things to find here. The second place is greener than almost anywhere else. The rain falls the heaviest in this place. The trees grow taller and thicker than the ones in cities. The air there is much fresher than in other places. Tip: Adjectives modify nouns, and adverbs modify verbs. Positives Comparatives Superlatives 概述: 大多数形容词和副词有三个等级:原级(positive), 比较级(comparative)和最高级(superlative)。 Read the sentences. Circle the adjectives which compare things. Underline the adverbs which compare actions. 4a What is the biggest desert in the world? It is the Sahara Desert. How big is it? It is about 9,000,000 square kilometres in size. Where is the deepest point in the ocean? It is in the Mariana Trench. How deep is it? It is about 11,000 metres deep. Some deep-sea animals are blind, but they can “see” as well as others. Mount Qomolangma is one of the greatest wonders of the world, and it is still growing taller. The Yangtze River travels the farthest in China and is about 6,300 kilometres long. 形容词/副词三个等级 原 级:形容词本来的样子,不比较 或A=B 只描述人 / 事物原本的特征、状态 比较级:比较两个事物,“A比B更...”A>B或A<B 最高级:三个或多个事物对比,“最...”A>B,C… the Yangtze River 长江 6300 km the Amazon River 亚马逊河 6440 km the Nile 尼罗河 6670 km long longer longest 形容词 / 副词本身的原形,不做任何比较, 只描述人 / 事物原本的特征、状态。 1 直接加 -er/-est(单音节 & 部分双音节) 原级 比较级 最高级 规则说明 tall taller tallest 直接加-er/-est large larger largest 以-e结尾,去e 加-er/-est big bigger biggest 重读闭音节辅元辅,双写末尾辅音字母 scary scarier scariest 以辅音+y结尾,变y为i加-er/-est 形容词/副词的比较级与最高级变化 大big 热hot天, 胖子fat瘦thin了, 瘦子纤细slim了,眼红red脸湿wet了 不是所有的形/副词都比较级 full, Chinese 2 前加 more/most(多音节 & 部分双音节) 原级 比较级 最高级 音节说明 beautiful more beautiful most beautiful 多音节 interesting more interesting most interesting 多音节 careful more careful most careful 双音节 famous more famous most famous 双音节 副词里,双音节的 slowly, quickly, carefully, happily + more / most。 early ==> earlier ==> earliest 原级 比较级 最高级 good (好的);well(好地) better best bad(糟糕的);badly(糟糕地) ill(生病的) worse worst many;much (许多的) more most little (很少的) less least far(远的) farther (强调距离) farthest further(强调程度) furthest old(老的) elder (强调长幼,只作定语) eldest older (强调年龄/新旧) oldest 口诀:两多两好三不好;一老一远加一少 3 不规则变化 1. tall _ _ 2. long _ _ 3. slow _ _ 4. large _ _ 5. late _ _ 6. big _ _ 7. happy _ _ 8. loud _ _ 9. easy _ _ 10. nice _ _ 11. amazing_ _ 12. quickly_ _ 13. well _ _ 14. little _ _ taller tallest longer longest slower slowest larger largest later latest bigger biggest happier happiest louder loudest easier easiest nicer nicest more amazing most amazing more quickly most quickly better best less least 比较级和最高级的构成 (1)规则变化 (2)不规则变化 2. 同级比较A=B ① A +系动词 + as + adj.原级+ as + B “A和B一样...” ② A +实义动词 + as + adv.原级+ as + B “A和B一样...” ① The lake is as deep as the sea. 一、形容词和副词的原级(不作比较) 他和他姐姐/妹妹一样努力工作。 ② He works as hard as his sister. 常用句型 否定:...not as+原级+as... “ A不如B....” 否定: The lake isn`t as/so deep as the sea. 否定: He doesn’t work as hard as his sister. the Yangtze River 1.A+ 谓 系动+形容词(原级) 实动+形容词(原级) The Yangtze River is very long. He runs really fast. too/very/quite/ so/pretty/more/most+原级 1. 比较级+ than 二、形容词和副词的比较级 A>B (1) A +be动词+ adj.比较级+than +B She is_ than me. (outgoing) Her shoes is _ than mine. (big) (2) A+实义动词 + adv.比较级+than +B He studies _than his classmates. (hard) 技巧:than 前比较级,than后用宾格 【注意】“形物代+名词”作主语时,than 后对象要统一 more outgoing bigger harder 比较对象一致 ① China is much older than the United States. 中国比美国古老得多。 修饰比较级的 词 ② She runs a lot faster than me. 她跑得比我快多了。 两多:_ 两少:_ 一甚至:_ 一还:_l 一远去:_ much; a lot a little; a bit even still Grammar Comparatives 比较级修饰词 常见的有much, a lot, a little, a bit, even, still, far等. far 助记口诀: 两 “多”两 “少”一 “甚至”, “还”有一个 “远”去了。 比较级 + and + 比较级 (单音节词/部分双音节词) more and more+ 原级(多音节词/部分双音节词) ① The earth is getting_ . 地球变得越来越暖和。 ② Wind blows up bags _in the sky. 风把袋子吹得越来越高。 ③ Online shopping is _ among young people. 网购在年轻人中越来越受欢迎。 warmer and warmer higher and higher more and more popular 2. “越来越……” 主+ 谓 the + 比较级 +(主+谓) …, the + 比较级 +(主+谓 )… ① The _ he is, the _ he feels. 他越忙越高兴。 ② The _ you run, the _you breathe. 你跑得越快,呼吸就越困难。 ③ The _you read, the _ you know. 你阅读得越多,知道的就越多。 busier happier faster harder more more 3.“越…,越…” 6. A+谓+数词 + times + 比较级 + than +B “…是…的几倍” Our school is twice bigger than yours. 4. 主+ 谓语+the + 比较级 + of the twins/two (+ 名复) “两者中,A较…的那个” Mike is the taller of the two boys. =Of the two boys, Mike is the taller. 迈克是两个男孩中较高的那个。 5. Which/Who... + 比较级, A or B? “ A和B哪个/谁更……?” Which city is_(large), Beijing or Shanghai? What would you like _ (well), apples or oranges? 我的学校是你的三倍。 larger better =Our school is _as _ as yours. three times big once/twice/ three times/four times 比较级 + than any other + 单数可数名词 + 其他 = 比较级+ than the other + 可数名词复数 + 其他 Qomolangma is higher than any other mountain in the world. = Qomolangma is the highest mountain in the world. 珠穆朗玛峰比世界上其他任何山峰都高。( = 珠穆朗玛峰是世界上最高的山峰。) Shanghai is bigger than any other city in China. This book is more popular than the other books in the library. 上海比中国其他任何城市都大。 这本书比图书馆里的其他书更受欢迎。 7.“比其他任何一个……都…… 比较级表最高级, 可与“the+最高级”相互转换 主+ 谓 …() 1. 主+ 系动词 + the + adj.最高级 (+名词) + of / in/among短语 主+ 实义动词+ (the) + adv.最高级+ of / in/among短语 三、形容词和副词的最高级 A>B,C ① The Nile is the longest river in the world. ② I think spring is the best time of a year. ③ She plays volleyball (the) best in her class. ④ Tom works (the) hardest among all the boys in Class 3. 2. one of the + adj.最高级 + 复数名词 “最……之一” She is one of the best tennis players in the world. 翻译:她是世界上最好的网球运动员之一。 in+范围 of +同类特定群体 among +同类事物 /人 + 谓单 3. A+be+the + 序数词 + adj.最高级 + 单数可数名词 +of / in/among短语 “是……中的第几……” The Amazon is _ in the world. 亚马逊河是世界上第二长的河流。 4. Which/Who...(the+) 最高级,A,B or C? “哪个/谁是最......,A,B还是C ?” Who sings _ (well) in your class, Lily, Tom or Jack? Who is _(outgoing), Lisa, Jack or Mike? Which subject do you like _ (well), English, maths or Chinese? best the most outgoing best the second longest river 【注意】 使用最高级时,前一般要加the; 但当最高级前有物主代词、指示代词、名词所有格等修饰时,则不加the. 形容词最高级作表语时,the 可省 副词最高级前 the 可加可省 Monday is my busiest day. That's Linda's best picture. This desert is (the) largest in Asia. The wind blows (the) strongest on the mountain top. My friends and I visited Victoria Falls in Africa last year. Visiting one of the world’s _ waterfalls was a magical experience. As we went _ to the falls, the noise of the water slowly grew _ and louder. Then, right before our eyes, the waterfall appeared. It went on for as _ as the eye could see. Later, we sat in a special pool at the top of the falls. There, we felt the water rush past us and become a part of the waterfall. It was the scariest but also the _ experience of our trip! 4c Complete the passage with the correct forms of the words in the box. largest large amazing far close loud closer louder far most amazing one of the + 最高级+cn复数 went closer 走近 比较级+and+比较级 as +原级+as the+最高级+范围 How does the writer make the description vivid? Tip: Find the answer by looking for “sensory words” — words that tell us what we see, hear, and feel. more/most close adj. 亲密的;接近的 adv. 接近地,靠近地 课本P35 Tip: 首先,把握文章整体语境。然后,关注空格前后词语搭配、语法结构,从方框中选择符合句意的单词并换成正确形式。最后,通读全文,检查语义、语法是否正确。 My friends and I visited Victoria Falls in Africa last year. Visiting one of the world’s _ waterfalls was a magical experience. As we went _ to the falls, the noise of the water slowly grew _ and louder. Then, right before our eyes, the waterfall appeared. It went on for as _ as the eye could see. Later, we sat in a special pool at the top of the falls. There, we felt the water rush past us and become a part of the waterfall. It was the scariest but also the _ experience of our trip! 4c Complete the passage with the correct forms of the words in the box. largest large amazing far close loud closer louder far most amazing Hearing(听觉) Sight(视觉) 它延伸得很远,一眼望不到边. Touch(触觉) My friends and I visited Victoria Falls in Africa last year. Visiting one of the world’s largest waterfalls was a magical experience. As we went closer to the falls, the noise of the water slowly grew louder and louder. Then, right before our eyes, the waterfall appeared. It went on for as far as the eye could see. Later, we sat in a special pool at the top of the falls. There, we felt the water rush past us and become a part of the waterfall. It was the scariest but also the most amazing experience of our trip! Language Points 世界上最大的瀑布之一 一次奇妙的经历 go closer to… 向…走近/靠近 水流的声音 grow louder and louder变得越来越响 就在我们眼前 目之所及(一眼望不到边) 在……的顶部 从我们身边冲过/流过 成为……的一部分 恰好;就在 匆匆经过 Language Points 1. Visiting one of the world's largest waterfalls was a magical experience. 游览世界上最大的瀑布之一是一次神奇的经历。 汤姆喜欢旅游,他有许多不寻常的经历。 Tom likes travelling. He has many unusual experiences. 格林老师有着丰富的教学经验。 Mrs Green has a lot of teaching experience. 儿童需要通过亲身经历来学习。 Children need to experience things for themselves to learn. experience ① 可数名词 (一次)经历,体验 ② 不可数名词 经验 ③ 及物动词 经历 Language Points 2. As we went closer to the falls, the noise of the water slowly grew louder and louder.当我们向瀑布走近时,水流的声音慢慢变得越来越响。 当我们走进教室时,同学们变得越来越安静。 As we walked into the classroom, the students grew quieter and quieter. 当冬天来临时,白天变得越来越短。 As winter comes, the days grow shorter and shorter. As 引导时间状语从句:当……的时候 3. There, we felt the water rush past us and become a part of the waterfall.在那里,我们感受到水流从我们身边冲过,成为瀑布的一部分。 I felt someone tap my shoulder.我感到有人拍了拍我的肩膀。 She felt tears run down her face. 她感到眼泪从脸上滑落。 feel sb./sth. do sth. 感官动词后接不带to的动词原形作宾补 词 讲 It went on for as far as the eye could see.它一眼望不到头。(教材P35 4c) as far as... 远至(某处) Language points 拓展:as far as... 就……的限度,到……的程度 相关短语&例句 as far as we know 据我们所知 as far as I can see 依我看 You’d better learn as much as you can. 你应该尽可能多地学习。 1. As far as we know, the Sahara is the biggest desert in the world. 据我们所知,撒哈拉沙漠是世界上最大的沙漠。 2.As far as I can see, there is no difference between the two computers. 依我看,这两台电脑没有差别。 4d Write some questions to compare places. Then ask a partner your questions. What is the highest ...? Which park is bigger, ... or ...? What is the deepest ...? What is the most famous ...? Which ... is longer, ... or ...? Which ... is higher, ... or ...? Is ... as deep as ...? Is ... as amazing as ...? 温馨提示:这个活动和后面的推荐官选其一即可哦 Sample A: Which park is bigger, Yellowstone National Park or Sanjiangyuan National Park? B: Sanjiangyuan National Park is much bigger. It covers around 123,100 square kilometres. Yellowstone is around 9,000 square kilometres. A: What is the longest river in the world? B: The Nile is the longest river in the world. A: Which is the largest desert in the world? B: The Sahara is the largest desert in the world. A: That’s interesting. And what is the highest building in our city? B: In our city, the highest building is a hospital. Summary Large numbers Positives Comparatives 1. 从右至左每三位分一节,依次为thousand(千)、million(百万)、billion(十亿);无“万”,用ten thousand表示,“十万”用one hundred thousand表示。 2. 百位和十位间加and(英式),百位数为0时,在thousand后加and。 3. 小数点读point,小数点后数字逐个读。 肯定结构: A + 谓语 + as + 原级 + as + B (A和B一样……) 否定结构: A + 谓语 + not as/so + 原级 + as + B (A不如B……) 1. A + 谓语 + 比较级 + than + B (A比B更……) 2. Which/Who + 谓 + 比较级, A or B? (A和B中,哪一个/谁更……?) 3. A + 谓 + the + 比较级 + of the two (两者中,A是更……的那一个) 4. The + 比较级 + 主谓, the + 比较级 + 主谓 (越……,就越……) 5. 比较级 + and + 比较级 / more and more + 原级 (越来越……) 6. 主语 + 谓语 + 比较级 + than any other + 单数名词 + 范围 = 主语 + 谓语 + 比较级 + than the other + 复数名词 + 范围 (……比同一范围内其他任何一个都……,表最高级) Summary Superlatives 1. 主语 + 谓语 + (the) + 最高级 + 范围 (……在某范围内最……) 2. 主语 + 谓语 + one of the + 形容词最高级 + 复数名词 + 范围 (……是……中最……之一) 3. 主语 + 谓语 + the + 序数词 + 形容词最高级 + 名词 + 范围 (……是……中第几最……的) 4. Which + 谓语 + (the) + 最高级, A, B or C? (A、B、C中,哪一个最……?) 同义转换 比较级 + than any other + 单数名词 + 范围 比较级 + than the other + 复数名词 + 范围 = the + 最高级 + 范围 用括号中所给单词的适当形式填空 1 1. For _ (far) information, please call Miss Smith on 139122066666. 2. It’s true that home is the _ (warm) place wherever we go. 3. On Friday afternoon, our school ends _ (early) than usual. 4. Mary does homework _ (careful) in her class and she always gets the best grades. 5. There are _ (many) people in the park today because the weather is better than yesterday. further warmest earlier (the) most carefully more 38 用所给词的适当形式填空 1.The Yellow River is _ (long) than the Huaihe River. 2.Mount Tai is the _ (high) of the two mountains in Shandong. 3.The sea is getting more and more _ (beautiful) with environmental protection. 4.This lake is the _ (deep) in our province. 5.Which is _ (long), the Amazon River or the Nile River? 6.This river is three metres _ (wide) than that one. 7.Hainan Island is the second _(large) island in China. 8.The sunset over the ocean is one of the _ (amazing) sceneries in the world. longer higher beautiful deepest longer wider largest most amazing 按要求完成下列各题 2 11. John plays basketball best of the boys in his class. (改为同义句) John plays basketball _ than _ _ _ in his class. 12. My brother is 14 years old. My cousin is 12 years old. (合并为一句) My brother is _ _ _ _ my cousin. 13. That is one of the most popular books. (改为反义句) That is one of _ _ _ books. 14. Simon is shorter than his brother. (改为同义句) Simon isn’t _ _ _ his brother. 15. Lisa is the most careful student in my class. (改为同义句) Lisa is _ _ _ any other student in my class. better any other boy two years older than the least popular as/so tall as more careful than 40 Homework Choose two natural wonders you know and compare them in detail using comparatives and superlatives, then share your findings with your classmates next time. Must-do Choose-to-do Write a short paragraph to describe your favourite natural wonder, using at least three comparatives and two superlatives. $