人教版新课标必修四第二单元warming-up-and-reading课件

1、2021/6/71 Chemical or organic farming? 2021/6/72 fertilizer. 2021/6/73 How many kinds of fertilizers do farmers use ? And what are they? There are two kinds. They are chemical fertilizers and natural waste from animals. 2021/6/74 Which kind do farmers use when they are doing organic farming ? The se

2、cond one-natural waste from animals 2021/6/75 Chemical or organic farming? 2021/6/76 Read the passage quickly and try to find out the main idea of the each paragraph. * Pay attention to the key word(s) in each paragraph. Task 1. Skimming 2021/6/77 D. Long-term use of chemical fertilizers can cause d

3、amage to the land and peoples health. C. Problems caused by chemical fertilizers. P1. P2. B. Farmers and customers turn to organic farming. A. Other methods to keep the soil fertile. P3. P4. Main idea of the each paragraph. 2021/6/78 Main idea of the passage _ fertilizers can cause many _, so organi

4、c farming is becoming more_. Chemical problems popular 2021/6/79 Reading Para1: Using chemical fertilizers can hurt the land and also peoples health. 1.Why are chemical fertilizers so popular in farming today? 2.Do you think it is really a great way? They are a great way to stop crop disease and inc

5、rease production. No 2021/6/710 What problems can be caused by using chemical fertilizers? (disadvantage) Firstly, they damage the land by killing the helpful bacteria and pests. Secondly, Chemicals staying in the ground and underground water for a long time affects crops and, therefore, animals and

6、 humans. And many of the chemicals can lead to cancer or other illnesses. Thirdly, fruit, vegetables and other food grown with chemical fertilizers usually grow too fast to be full of much nutrition. Para2: Problems caused by chemical fertilizers 2021/6/711 1.What is organic farming? 2. What is the

7、advantage of using natural fertilizer? Para3: Organic farming is becoming more popular with some farmers and many customers 2021/6/712 1.What is organic farming? Organic farming is simply farming without using any_. green food chemicals 2021/6/713 2. What is the advantage of using natural fertilizer

8、? * Reduce diseases in crops and help them grow strong and healthy. * Make the soil richer in minerals and so more fertile. * Besides, keep the air, soil and water as well as the food supply free from chemical. 2021/6/714 Para4: Other methods to keep the soil fertile. How many methods are mentioned

9、in this paragraph? And what are they? 2.What is the same goal of these different organic farming methods? 3.Why do organic farmers grow peas or soybeans after corn or wheat? 2021/6/715 How many methods are mentioned in this paragraph? And what are they? Change the kind of crop in each field every fe

10、w years. Three 2) Plant crops to use different levels of soil. 3) Plant grass between crops and leave it in the ground. 2.What is the same goal of these different organic farming methods? The same goal is to grow good food and avoid damaging the environment or peoples health. 2021/6/716 Farmers grow

11、 peas or soybeans after corn or wheat so that peas and soybeans can put important minerals back into the soil, making it ready for crops such as wheat or corn that need rich and fertile soil. 3.Why do organic farmers grow peas or soybeans after corn or wheat? 2021/6/717 Answers to Exercise 2 on P15:

12、 Methods of organic farming Advantages of methods 1.Farmers use natural waste from animals 2.Farmers change the kind of crop in each field every few years. 3.Farmers plant crops with different lengths of roots. 4. Farmers plant grass between crops and leave it in the ground. Changing the crops renew

13、s the _in the soil and helps it become _ and _. This prevents _ or _ from _ _soil and acts as a _fertilizer. This uses different _ of soil. This makes the soil _in _and so more_. richer mineralsfertile minerals richfertile levels wind water carrying away natural 2021/6/718 In recent days, scientists

14、 have discovered that using_ fertilizers for a long time can hurt the land and also peoples _. There are several _ caused by chemical fertilizers. They hurt the health of the land,_ in the water for a long time and get into peoples _ through their food. chemical bodies problemshealth stay Fill in th

15、e blanks according to the passage. Retelling 供应供应”等等 supply and demand 供与求供与求 be in short supply 供应缺乏供应缺乏,供应不足供应不足 food supply 食物供应食物供应 water supply 供水供水 2021/6/724 2) 用作动词时用作动词时,指指“供给供给,提供提供,备办备办”等等, supply sb._ sth , sth._ sb. with to /for offer provide sth _ sb sb _ sth to for with sth _ sb sb _

16、sth 2021/6/725 When I meet difficulty, my roommates will_ me help. offer The government need to _ food and clothes for these old people provide All the rooms are _ with electric lights. A. supplied B. given C. offered D. burnt 2021/6/726 6. build up 逐渐积聚逐渐积聚; 增进，增强增进，增强 来往的车辆在通往市区的路上越聚越多。来往的车辆在通往市区的

17、路上越聚越多。 Traffic is building up on roads into the city. build up ones health/body 增强体质增强体质,锻炼身体锻炼身体 7. lead to (leadledled ) 通向通向;导致（某种）结果；造成导致（某种）结果；造成 This road leads to the railway station. His mistakes led to his failure. All roads lead to Rome. 条条大路通罗马条条大路通罗马 2021/6/727 8.in addition (to) 除除之外之外

18、;此外此外;并且并且 We met some friends and other people _ _. _ the killed and wounded, many were missing. _, I want to tell you something about Tom. in In addition to In addition addition in addition 常放常放在句首在句首, ,用逗号隔开用逗号隔开, ,或放在或放在句末句末. . in addition to后面常跟后面常跟名词或名词短语名词或名词短语 2021/6/728 9.They focus on keep

19、ing their soil rich and free of disease. focus on : 集中（注意力、精力）于集中（注意力、精力）于 把注意力集中在你工作上把注意力集中在你工作上. Focus your attention on your work. All eyes were focused on him. 2021/6/729 10.keepfree of /from: protect. from 使免受（影响使免受（影响,伤害等）伤害等） 健康饮食和锻炼使你远离感冒。健康饮食和锻炼使你远离感冒。 Healthy eating and good exercise keep you free from/of cold. 11. reduce_ 减少减少/降低降低了了 reduce _ 减少减少/降低降低到到to by 12. every few years 每隔几年每隔几年 13. put sth back into 将将带回到带回到 14. use differen