人教版新课标必修四第二单元warming up and reading课件教材课程.ppt

Chemical or organic farming?; What is the thing we put on the soil which makes crops grow ? It is fertilizer. ; 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.; Which kind do farmers use when they are doing organic farming ? ;Chemical or organic farming?;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.;D. Long-term use of chemical fertilizers can cause damage to the land and people’s health.;Main idea of the passage;;1.What is organic farming? 2. What is the advantage of using natural fertilizer?;1.What is organic farming?;2. What is the advantage of using natural fertilizer? ;Para4: Other methods to keep the soil fertile.;How many methods are mentioned in this paragraph? And what are they?;Farmers grow 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.;Answers to Exercise 2 on P15:;; ________ farming is becoming more popular with some farmers and many _________ after these discoveries came out. Organic farming does not use any chemicals. There are many organic farming_________ for making the land healthy and productive. All of these methods try to produce good food and to keep the _____________and people ________. ;Suppose you were given a farm. What would you like to grow or raise? How would you deal with your farming?;Language points; 1.over/in the past half century 在过去的半个世纪里; 5.These chemicals in the food supply build up in people’s bodies over time.;2) 用作动词时,指“供给,提供,备办”等, supply sb.____ sth , sth._______ sb. ;When I meet difficulty, my roommates will_____me help.;6. build up 逐渐积聚; 增进，增强 ; 8.in addition (to) 除…之外;此外;并且;9.They focus on keeping their soil rich and free of disease