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

Section A (4a-4c) Made by Qianmo-studio The Wonders of Nature Unit 4 1 1. To review the usage of the comparatives and superlatives. 2. To master the rules about how to read large numbers in English. 3. To talk about more natural wonders and places using the target language. Learning objectives Read the sentences. Circle the adjectives which compare things. Underline the adverbs which compare actions. 4a Presentation 1.Mount Kilimanjaro is________ (five thousand, eight hundred and ninety-five) metres high. 2.__________ (twenty-five thousand, seven hundred and sixty- eight) cubic metres of water pours down Inga Falls each second. 3.The East African Rift Valley is about 4,000 (______________) miles long. 4.The Taklimakan Desert has a total area of about 337,000 (____________________________________) square kilometres. 5, 895 three hundred and thirty-seven thousand 25, 768 four thousand 总面积为…… Write or spell out the numbers. 4b /ˈkjuːbɪk/ 立方米 Practice thousand million 1.从数字的右端向左数，每三位数加一个逗号。 2.从右向左，第一个逗号处读thousand（千），第二个逗号处读million（百万），第三个逗号处读billion（十亿）。 3.读数时，通常在hundred后加and；若百位数为0，则在thousand后加and。 4.英语中无直接表示“万”和“亿”的单位词，需用thousand和million表达，如“一万”是ten thousand、“一亿”是one hundred million。 四、较大数字的表达与读法 9，365,278,689 billion 注意： 小数点读作“point”，小数点左边的数按整数读法读，右边的数依次读出每个数字。 例如:3.14读作“three point one four” 8848.86 读作“eight thousand，eight hundred and forty-eight point eight six" . Presentation 写出或读出下列数字。 2,674 → ______________________________________________ 164,213,430 → ________________________________________ _________________________________________ 18,357,089 → _________________________________________ __________________________________________ twenty-eight thousand, six hundred and fifty-six ___________ forty million, four hundred and twenty-four thousand _______ two thousand six hundred and seventy-four one hundred and sixty-four million, two hundred and thirteen thousand, four hundred and thirty eighteen million, three hundred and fifty-seven thousand, and eighty-nine 28,656 40,424,000 Practice Complete the passage with the correct forms of the words in the box. large amazing far close loud 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! largest close louder far most amazing 4c ......远至（某处） /ˈkjuːbɪk/ adj. 立方的 Practice 词 讲 练 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） Everything is possible ________ you work hard. A. as much as B. as soon as C. as long as D. as far as 拓展：as far as... 就……的限度，到……的程度 相关短语&例句 as far as I/we know 据我/我们所知 as/so far as I can see 依我看 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。 D Language points 一、比较级(用于两者之间的比较)用法 形容词或副词的比较级+than The Changjiang River is longer than it.长江比它长。 Bill runs faster than any other boy in his class.比尔跑得比班上其他任何男孩都快。 “比较级+and+比较级(单音节词和部分双音节词)” 或“more and more+原级(多音节词和部分双音节词)”表示“越来越……”。 Summer is coming. It's getting hotter and hotter.夏天就要来了。天越来越热了。 Our hometown is becoming more and more beautiful. 我们的家乡变得越来越美丽。 “the +比较级...，the+比较级..”表示“越……,就越……”。 The more you read, the more you know. 你阅读得越多,知道的就越多 the + 比较级 + of the two (+ 名词复数) 表示“两者中较……的那个”。 Mike is the taller of the two boys. 迈克是两个男孩中较高的那个。 Which/Who... + 比较级, A or B? 表示“ A和B哪个/谁更……？” Which city is larger, Beijing or Shanghai? 北京和上海，哪个城市更大？ Presentation 二、 最高级(用于三者或三者以上的比较)的用法： ①the+形容词的最高级＋of/in... He is the tallest of the three. 他是这三个人中最高的。 He is the funniest in his class. 他是他们班最有趣的。 ②one of the+形容词最高级+可数名词复数＋of/in... ……中最……的……之一 Pingyao Ancient City is one of the best-kept ancient cities in China. 平遥古城是中国保存最完好的古城之一。 ③Which/Who ...+(the) +最高级, A, B or C ? Who sings the best in your class, Lily,Tom or Jack? 你们班谁唱的最好，莉莉、汤姆还是杰克？ the +序数词+形容词最高级+可数名词单数+in/of 短语, 意为“在…中是第几……的……” The Yellow River is the second longest river in China. 黄河是中国第二长河。 Presentation 三、形容词、副词比较级、最高级构成： 一、 规则变化 ①一般情况下，单音节或双音节的形容词(或副词）比较级＋er ，最高级＋est clever－cleverer－cleverest few－fewer－fewest small－smaller－smallest ②以e结尾的词，比较级＋r，最高级＋st nice－nicer－nicest cute－cuter－cutest large－larger－largest ③以“辅音字母＋y”结尾的变y为i＋er或est easy－easier－easiest happy－happier－happiest ④多音节和部分双音节词在形容词原级前＋more构成比较级，＋the most构成最高级。 beautiful－more beautiful－the most beautiful careful－more careful－the most careful Presentation 不规则变化 good/ well －better－best bad/badly－worse－worst many/much－more－most little －less－least far－farther－farthest (距离远) far－further－furthest (程度深) old－elder－eldest (长幼) old－older－oldest (年龄) Tips： 一好一坏； 一多一少； 一远一老 Presentation 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 Practice Sum up what you have learned. 形容词和副词的比较级与最高级 较大数字的表达 规则变化、不规则变化 比较级和最高级的构成 比较级的用法 最高级的用法 1. 比较级+than 2. the + 比较级, the + 比较级 3. 比较级 + and + 比较级 more and more + 形容词/副词原级 1. (the +) 最高级 + in/of/among短语 2. one of the + 形容词最高级 + 可数名词复数 + in/of短语 3. “Which/Who...(+the)+最高级, A, B or C?” 4. the + 序数词 + 形容词最高级 + 可数名词单数 + in/of短语 thousand million billion 9，365,278,689 Summary 一、用所给词的适当形式填空。 1.Lin Tao runs ________(fast) than his classmates. He is the running star in his class. 2.The more we communicate with our parents, the _______(good) we'll understand each other. 3.Miss Li always has a lot of work to do. For her, nothing is _______________(important) than a proper plan. 4.For most of the students, June is always the ________(busy) month in a year. 5.Qian Xuesen, father of China's space program, is one of the ________(great) scientists in the world. faster better more important busiest greatest Exercises 二、单项选择 1.The National Library of China is ______ public library in Asia. A. large B. larger C. largest D. the largest 2. In a DIY club, the more we practice, ______ we become. A. the worse B. the worst C. the better D. the best 3. Journey to the West is one of ______ classic novels in China. People like reading it. A. famous B. more famous C. the more famous D. the most famous 4. It is said that smart technology is making people ______ than before and doing them harm. lazy B. lazier C. laziest D. the laziest 3.The forest is becoming ______ because more trees are planted every year. A. greener and greener B. green and green C. more and more green D. greenest D C D B A Exercises 1. Memorize the summary 2. Recite the grammar focus. Homework Homework $