人教版英语必修4Unit2第3学时：UsingLanguage：Readinglisteningandspeaking课件.ppt

第三学时　Using Language Reading，listening and speaking;Task 1;Task 2;2．From the fourth paragraph，we know that ________. ( ) A．it’s not good to plant grass between crops B．peanuts use the surface of soil C．peas and soybeans should be grown together with corn and wheat D．vegetables that put down deep roots are harmful to the soil;3．According to the text，which of the following is NOT the problem caused by chemical fertilizer? ( ) A．Crop diseases can be stopped. B．Chemicals stay in the ground and underground water for a long time. C．The helpful bacteria and pests are killed as well as the harmful one. D．Many of these fertilizers are dangerous to people’s health. 4．How many ways do the organic farmers have to keep their soil fertile and healthy? ( ) A．3　　　B．4　　　C．5　　　D．6;Part A Role Play; Q2: 使用化肥会导致什么问题？ ________________________________________________________________________ Q3: 什么是有机耕作？ ________________________________________________________________________ Q4: 有机耕作有什么好处？ ________________________________________________________________________;Part A Role Play  Q1:Why are chemical fertilizers so popular in farming today? A1:Because they are a great way to stop crop disease and increase production. Q2:What problems can be caused by using chemical fertilizers? A2: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 people’s health by building up in their bodies and leading to cancer or other illnesses.;Q3:What is organic farming? A3:Organic farming means growing crops without using any chemicals. Q4:What are the advantages of using organic farming methods? A4:The advantages of using organic farming methods are to grow good food and avoid damaging the environment or people’s health.;Part B　Retelling;Part B Retelling  Many farmers use chemical fertilizers as a great way to stop crop disease and increase production. But they can