人教版高中英语必修4 Unit2 Using language 名师精品课件

1、What is the substance we put on the soil which makes crops grow?It is fertilizer. How many kinds of fertilizers do farmers 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? ORGANI

2、C FARMING Organic farming is simply farming without using any chemicals.Scan the passage and get the main idea.Chemical fertilizers can cause many problems, so organic farming is becoming more popular.1. Why are chemical fertilizers so popular in farming today?Answer the following questions after re

3、ad the passage.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 water for a long time. They damage peoples health

4、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 using organic farming methods is to grow good food and

5、 to avoid damaging the environment or peoples health. Read the passage carefully and fill in the blanks.Chemical FarmingAdvantagesStopping crop disease and increase _productionChemical FarmingDisadvan-tagesDamaging the land: killing the helpful _ Damaging peoples health:Many chemicals in the food su

6、pply 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 farmingMethodsUsing _ waste from animals as fertilizer Changing _ in each field every few

7、years Using _ of soil to plant crops Planting _ between cropsgrassnaturalthe kind of cropdifferent levelsIn what condition do you think green food grow?dirty air dirty water supplies in industrial areas many chemical fertilizersclean, fresh air clean water supplies away from industrial areas free of

8、 chemical fertilizersPersuade farmers to grow the crops by organic farming with the knowledge you have learnt. What is organic farming? What fertilizer should they use? Why? How to plant the different crops? .1. Many of these chemicals can lead to cancer. 很多化学成份能导致癌症很多化学成份能导致癌症 阅读下列句子阅读下列句子, 注意注意lea

9、d to的意思和用法。的意思和用法。 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 often leads to illness.自我归纳自我归纳 lead to意为意为“_”, 后多跟名后多跟名词或代词。词或代词。导致、造成导致、造成(后果后果)联想联想 result in引起引起(某种结果某种结果)、使获得、使获得(某种成果某种成果)、结果结果

10、 如：如：The accident resulted in two deaths.result from 由由造成、因造成、因而产生而产生如：如：Sickness sometimes results from eating too much.即学即练即学即练 用用lead to的适当形式完成句子。的适当形式完成句子。1) Students should always remember that hard work is the main way which _ success.2) The bad weather _ a terrible accident a few days ago.led

11、 toleads to2. They focus on keeping their soil rich and free of disease. 农民关心的是保持土壤肥沃并且免农民关心的是保持土壤肥沃并且免受病害。受病害。 根据语境推断根据语境推断focus在下列句子中的在下列句子中的含义含义, 并从并从a-d中找出与每句话中的中找出与每句话中的focus相符合的英文释义。相符合的英文释义。1. The focus of the meeting changed from population growth to the education of women.2. Bring the objec

12、t 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.c abda. the thing, person, situation, etc. that people pay special attention tob. a point or distance at which the outline of an object is clearly seen by the

13、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 n. 焦点、中心点焦点、中心点 v. 集中、聚焦集中、聚焦focus on 集中集中(注意力、精力等注意力、精力等)于于翻译翻译1) Because of

14、 his strange clothes, he immediately became the focus of attention when he entered the office. 由于他的奇装异服由于他的奇装异服, 所以一走进办公所以一走进办公室他便成了大家注意的焦点。室他便成了大家注意的焦点。2) Focus your camera on those trees.3) Im so tired that I cant focus on anything today.把照相机的焦点集中在那些树上。把照相机的焦点集中在那些树上。今天我太累了今天我太累了, 精神集中不起来。精神集中不起来。

15、3. This also keeps the air, soil, water and crops free from chemicals. 同时还可以让空气、土壤、水以及农作物同时还可以让空气、土壤、水以及农作物不受化学物质的污染。不受化学物质的污染。 keep free from 远离，避免远离，避免keep free from emotional reactions 避免激动的反应避免激动的反应 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

16、back into the soil, making it ready for crops such as wheat or corn that need rich and fertile soil. 像豌豆或大豆这样的农作物将重要的像豌豆或大豆这样的农作物将重要的矿物质带回土壤，从而使之适宜于种矿物质带回土壤，从而使之适宜于种植要求土壤肥沃的农作物。植要求土壤肥沃的农作物。分析分析 本句结构比较复杂。其本句结构比较复杂。其主干结构为主干结构为: 主主句句(Crops put important minerals back into the soil) + 状语状语(making it rea

17、dy for crops)。状语中又包含状语中又包含“make + it + 形容词形容词”结结构和由构和由that引导的定语从句引导的定语从句(that need rich and fertile soil)。 5. Some organic farmers prefer planting grass between 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 y

18、ears crop. 还有一些有机耕作者喜欢在农作物之间还有一些有机耕作者喜欢在农作物之间种草，以防止水土流失，并且把草流在种草，以防止水土流失，并且把草流在地里，从而成为来年农作物的天然肥料。地里，从而成为来年农作物的天然肥料。分析分析本句的主干结构是一个简单句本句的主干结构是一个简单句, 其结构是其结构是: 主主 语语(farmers) + 谓语谓语(prefer) + 并列宾语并列宾语 (planting . + leaving .)。其中其中between crops和和in the ground作地点状语。作地点状语。两个宾语后面又分别带有一个不定式作目的两个宾语后面又分别带有一个不

19、定式作目的状语状语(to prevent wind or water from carrying away the soil 和和 to become a natural fertilizer for the next years crop)。What is the main topic of the conversation?The possible bad effects of chemical fertilizers on the fruit and vegetables that we eat today. 1. Paul thinks that Carrie is not telling him the truth.2. Using chemical fertilizers always makes vegetables empty inside.3. Todays fruit is not as healthy for people as fruit fifty years