人教版必修四U2Usinglanguage

1、Unit2 CHEMICAL OR ORGANIC FARMING? 化化學(xué)耕作還是有機耕作？學(xué)耕作還是有機耕作？Over the past half century, using chemical fertilizers has become very common in farming. 在過去的半個在過去的半個世紀(jì)里，在耕作中使用化肥已經(jīng)非常普遍。世紀(jì)里，在耕作中使用化肥已經(jīng)非常普遍。Many farmers welcomed them as a great way to stop crop disease and increase production. 很多農(nóng)民喜歡使用很多農(nóng)民喜歡使

2、用化肥。把化肥作為防治農(nóng)作物病蟲害和提高產(chǎn)量的化肥。把化肥作為防治農(nóng)作物病蟲害和提高產(chǎn)量的重要手段。重要手段。 Recently, however, scientists have been finding that long-term use of these fertilizers can cause damage to the land and, even more dangerous, to peoples health. 然而，最近科學(xué)家發(fā)現(xiàn)長期使用然而，最近科學(xué)家發(fā)現(xiàn)長期使用這些肥料會造成土地受損，甚至更危險的是，會對這些肥料會造成土地受損，甚至更危險的是，會對人們的健康造成危害。

3、人們的健康造成危害。What are some of the problems caused by chemical fertilizers? 化肥帶來的問題有哪些呢？化肥帶來的問題有哪些呢？ First, they damage the land by killing the helpful bacteria and pests as well as the harmful ones. 首先，化肥在殺死病菌和害蟲的同時也會殺死有益首先，化肥在殺死病菌和害蟲的同時也會殺死有益的細菌和昆蟲，從而破壞土地。的細菌和昆蟲，從而破壞土地。Chemicals also stay in the groun

4、d and underground water for a long time. 化學(xué)物質(zhì)還會在地里和地下水中保存很化學(xué)物質(zhì)還會在地里和地下水中保存很長時間，長時間，This affects crops and, therefore, animals and humans, since chemicals get inside the crops and cannot just be washed off. 而這會影響到莊稼，進而影響到動物和人類，因為而這會影響到莊稼，進而影響到動物和人類，因為化學(xué)成分會進入到農(nóng)作物中，并且不能被沖洗掉。化學(xué)成分會進入到農(nóng)作物中，并且不能被沖洗掉。These

5、chemicals in the food supply build up in peoples bodies over time. 隨著時間的推移，隨著時間的推移，食物中的這些化學(xué)成分會在人體中堆積。食物中的這些化學(xué)成分會在人體中堆積。Many of these chemicals can lead to cancer or other illnesses. 很多化學(xué)成分能導(dǎo)致癌癥或其他疾病。很多化學(xué)成分能導(dǎo)致癌癥或其他疾病。 In addition, fruit, vegetables and other food grown with chemical fertilizers usual

6、ly grow too fast to be full of much nutrition. 另外，施過另外，施過化肥的水果、蔬菜和其他食物通常生長得過快而營化肥的水果、蔬菜和其他食物通常生長得過快而營養(yǎng)不足。養(yǎng)不足。 They may look beautiful, but inside there is usually more water than vitamins and minerals. 它們表面上很好看，但里面通常是含過它們表面上很好看，但里面通常是含過多的水分，而不是維生素和礦物質(zhì)。多的水分，而不是維生素和礦物質(zhì)。With these discoveries, some far

7、mers and many customers are beginning to turn to organic farming. 由于這些發(fā)現(xiàn)，由于這些發(fā)現(xiàn)，一些農(nóng)民和消費者開始轉(zhuǎn)向有機耕作。一些農(nóng)民和消費者開始轉(zhuǎn)向有機耕作。 Organic farming is simply farming without using any chemicals. 有機耕作就有機耕作就是不用任何化學(xué)肥料的耕作。是不用任何化學(xué)肥料的耕作。They focus on keeping their soil rich and free of disease. 農(nóng)民關(guān)心的是保持土壤肥沃并且免農(nóng)民關(guān)心的是保持土壤肥沃

8、并且免受病害。受病害。A healthy soil reduces disease and helps crops grow strong and healthy. 健康的土壤會減少病蟲害并且?guī)椭r(nóng)作物茁健康的土壤會減少病蟲害并且?guī)椭r(nóng)作物茁壯成長。壯成長。 Organic farmers, therefore, often prefer using natural waste from animals as fertilizer. 因此，有機耕作因此，有機耕作的農(nóng)民通常喜歡把天然的動物糞便當(dāng)作的農(nóng)民通常喜歡把天然的動物糞便當(dāng)作肥料。肥料。 They feel that this makes

9、the soil in their fields richer in minerals and so more fertile. 他們認(rèn)為這樣會使他們認(rèn)為這樣會使地里的土壤更富含礦物質(zhì)，因而也會更地里的土壤更富含礦物質(zhì)，因而也會更加肥沃，加肥沃， This also keeps the air, soil, water and crops free from chemicals.同時還可以讓空氣、土壤、水以及農(nóng)作同時還可以讓空氣、土壤、水以及農(nóng)作物不受化學(xué)物質(zhì)的污染。物不受化學(xué)物質(zhì)的污染。 Organic farmers also use many other methods to keep

10、the soil fertile. 有機耕作的農(nóng)民也使用很多其他有機耕作的農(nóng)民也使用很多其他的方法來保持土地肥沃。的方法來保持土地肥沃。They often change the kind of crop in each field every few years, for example, growing corn or wheat and then the next year peas or soybeans. 在同一塊地里，他們經(jīng)常每隔幾年就換在同一塊地里，他們經(jīng)常每隔幾年就換種農(nóng)作物。種農(nóng)作物。 例如，種玉米和小麥后來年再改種豌豆或例如，種玉米和小麥后來年再改種豌豆或大豆。大豆。 Cr

11、ops such as peas or soybeans put important minerals back into the soil, making it ready for crops such as wheat or corn that need rich and fertile soil. 像豌豆或大豆這樣的農(nóng)作物將重像豌豆或大豆這樣的農(nóng)作物將重要的礦物質(zhì)帶回土壤，從而使之適宜于種植要求土地肥要的礦物質(zhì)帶回土壤，從而使之適宜于種植要求土地肥沃的農(nóng)作物，比如玉米或小麥。沃的農(nóng)作物，比如玉米或小麥。Organic farmers also plant crops to use dif

12、ferent levels of soil, for example, planting peanuts that use the grounds surface followed by vegetables that put down deep roots. 有機耕作的農(nóng)民還種植多有機耕作的農(nóng)民還種植多種農(nóng)作物來利用不同層次的土壤。比如，他們先種植種農(nóng)作物來利用不同層次的土壤。比如，他們先種植生長于淺層土壤的花生，然后再種植生根于深層土壤生長于淺層土壤的花生，然后再種植生根于深層土壤的蔬菜。的蔬菜。Some organic farmers prefer planting grass betw

13、een crops to prevent wind or water from carrying away the soil, and then leaving it in the ground to become a natural fertilizer for the next years crop還有一些有機耕作者喜歡在農(nóng)作物之還有一些有機耕作者喜歡在農(nóng)作物之間種草，以防止水土流失，并且把草留在地里，從而間種草，以防止水土流失，并且把草留在地里，從而成為來年農(nóng)作物的天然肥料。成為來年農(nóng)作物的天然肥料。These many different organic farming methods

14、 have the same goal: to grow good food and avoid damaging the environment or peoples health. 這些不同的有機耕作這些不同的有機耕作的方法有著同樣的目標(biāo)：種植好的糧的方法有著同樣的目標(biāo)：種植好的糧食，避免損害環(huán)境或者人們的健康。食，避免損害環(huán)境或者人們的健康。 What is the substance we put on the soil which makes crops grow? It is fertilizer. How many kinds of fertilizers do farmers

15、use? There are two kinds. They are chemical fertilizers and natural ones. Which kind do farmers use when they are doing organic farming? Do you know about organic farming? ORGANIC FARMING Organic farming is simply farming without using any chemicals.1. Why are chemical fertilizers so popular in farm

16、ing today?I. Read the passage and answer the following questions.They are a great way to stop crop disease and increase production.2. What problems can be caused by using chemical fertilizers?They can damage the land by killing helpful bacteria and pests and by staying in the ground and underground

17、water for a long time. They damage peoples health by building up in their bodies and leading to cancer or other illnesses.3. What is organic farming? Organic farming means growing crops without using any chemicals.4. What is the main reason for using organic farming methods? The main reason for usin

18、g organic farming methods is to grow good food and to avoid damaging the environment or peoples health. II. Read the text again and fill in the blanks.Chemical FarmingAdvantages Stopping crop disease and increase _productionChemical FarmingDisadvantagesDamaging the land: killing the helpful _ Damagi

19、ng peoples health:Many chemicals in the food supply can lead to cancer or other illnesses.Food grows too fast to be full of much _.bacteria and pestsnutritionOrganic farming_To grow good food and avoid damaging the environment or peoples healthGoalOrganic farmingMethods Using _ waste from animals as

20、 fertilizerChanging _ in each field every few years Using _ of soil to plant crops Planting _ between cropsgrassnaturalthe kind of cropdifferent levelsIn what condition do you think green food grow?The advantages of green fooddirty air dirty water supplies in industrial areas many chemical fertilize

21、rsclean, fresh air clean water supplies away from industrial areas free of chemical fertilizersMain idea of the passageChemical fertilizers can cause many problems, so organic farming is becoming more popular.ORGANIC FARMINGStructure of the textI using chemical fertilizers for a long time can hurt t

22、he land and also peoples healthII Problem caused by chemical fertilizers1. Damage the land by killing the helpful bacteria and pests as well as the harmful ones2. Lead to cancer or other illness.3. Food grown with chemical fertilizers look beautiful, but inside there is usually more water than vitam

23、ins and minerals. Organic farming is becoming more popular with some farmers and many customers after these discoveries came out. IV Other methods to keep the soil fertile.ProjectPersuade the farmers in our county to grow the crops by organic farming with the knowledge learnt. What is organic farmin

24、g? What fertilizer should they use? Why? How to plant the different crops? Language points1. lead to用法用法寓詞于境寓詞于境 閱讀下列句子，注意閱讀下列句子，注意lead to的意的意思和用法。思和用法。1. His carelessness led to the accident.2. This test is obviously bad because it leads to incorrect learning.3. Too much work and too little rest of

25、ten leads to illness.自我歸納自我歸納 lead to意為意為“_”, 后多跟名詞或代詞。后多跟名詞或代詞。導(dǎo)致、造成導(dǎo)致、造成(后果后果)聯(lián)想聯(lián)想 result in引起引起(某種結(jié)果某種結(jié)果)、使獲得、使獲得(某種某種成果成果)、結(jié)果、結(jié)果。如：。如：The accident resulted in two deaths.result from由由造成、因造成、因而產(chǎn)生。如：而產(chǎn)生。如：Sickness sometimes results from eating too much.即學(xué)即練即學(xué)即練 用用lead to的適當(dāng)形式完成句子。的適當(dāng)形式完成句子。1. Stud

26、ents should always remember that hard work is the main way which _ success.2. The bad weather _ a terrible accident a few days ago.led toleads to2. focus用法用法 根據(jù)語境推斷根據(jù)語境推斷focus在下列句子中的在下列句子中的含義含義, 并從并從a-d中找出與每句話中的中找出與每句話中的focus相符合的英文釋義。相符合的英文釋義。1. The focus of the meeting changed from population growt

27、h to the education of women.2. Bring the object into focus if you want a clear photograph. 3. She tried to focus her mind on her work.4. She turned the camera and focused on Martins face.a. the thing, person, situation, etc. that people pay special attention tob. a point or distance at which the out

28、line of an object is clearly seen by the eye or through a lensc. to point a camera at something, and change the controls slightly so that you can see that thing clearly d. to give special attention to one particular person or thing, or to make people do thisfocus作名詞作名詞, 意為意為“焦點、中心點焦點、中心點”; 作動詞作動詞, 意

29、為意為“集中、聚焦集中、聚焦”, 常構(gòu)成短常構(gòu)成短語語focus on, 意為意為“集中集中(注意力、精力注意力、精力等等)于于”。翻譯下列句子。翻譯下列句子。1. Because of his strange clothes, he immediately became the focus of attention when he entered the office. 由于他的奇裝異服由于他的奇裝異服, 所以一走進辦所以一走進辦公室他便成了大家注意的焦點。公室他便成了大家注意的焦點。2. Focus your camera on those trees.3. Im so tired tha

30、t I cant focus on anything today.把照相機的焦點集中在那些樹上。把照相機的焦點集中在那些樹上。今天我太累了今天我太累了, 精神集中不起來。精神集中不起來。3. keep free from “遠離遠離”或或“避避免免”keep free from emotional reactions 避免激動的反應(yīng)避免激動的反應(yīng) keep free from restrictions 避免受到限制避免受到限制4. Crops such as peas or soybeans put important minerals back into the soil, making i

31、t ready for crops such as wheat or corn that need rich and fertile soil. 分析分析 本句結(jié)構(gòu)比較復(fù)雜。其主干結(jié)構(gòu)為本句結(jié)構(gòu)比較復(fù)雜。其主干結(jié)構(gòu)為: 主句主句(Crops put important minerals back into the soil) + 狀語狀語(making it ready for crops)。狀語中又包含狀語中又包含“make + it + 形容詞形容詞”結(jié)構(gòu)和由結(jié)構(gòu)和由that引導(dǎo)的定語從句引導(dǎo)的定語從句(that need rich and fertile soil)。 5. Some organic