背景介绍: 目前世界上最主要的沙尘暴是亚洲沙尘暴,影响范围覆盖了蒙古、中国、日本、韩国、哈萨克斯坦等国家 据有关部门提供的材料,在我国特大沙尘暴90年代至今已发生过20多次,并且波及的范围愈来愈广,造成的损失愈来愈重。 如XX年3月15日下午,沙尘飞至北京,持续达49小时,分布高度为3500米左右。 3月20日第二次袭击北京,持续长达51小时,此次沙尘暴北京总降尘量高达3万吨,相当于人均2公斤。这是20世纪90年代以来范围最大、强度最强、影响最严重、持续时间最长的沙尘天气过程, 袭击了我国北方140多万平方公里的大地,影响人口达1.3亿。 一、课前预习导学:(一)学习目标:1)掌握本文的11个新单词的音、形、义;(单词见生词表)2)充分理解课文大意并回答课本提出的问题;3)搜集关于“沙尘暴”的材料,了解其形成与危害及应对措施。(二)预习内容: 1.背熟生词,完成33页第2题2 课文内容预测:看题目“sandstorms in asia”及插图,预测课文内容,并预读了解大意。二. 课堂学习研讨 (一)课文阅读和理解: 略读方法: 1. 浏览标题 2. 读首段,抓中心思想。3. 浏览其他段首末句。4. 最后读结尾段。1略读, 找出各段大意(连线): para.1 a. the description of sandstorms para.2 b. the causes of sandstorms para.3 c. a major disaster in asia para.4 d. the effects of sandstorms para.5 e. the government’s measurespara.6 f. the forecast and suggestions 2查读:回答问题 查读方法:1先看题,明确查询细节的特点2快速查读,找到关键词 3停下细读,理清答案1)what is a sandstorm? 共3页,当前第1页1232)what is the cyclist wearing and why? (看32页图)3)what happens to traffic in sandstorms?4)what do experts suggest people to do in sandstorms?3细读: 填空归纳causeseffectssuggestionsmeasures4研读:语篇理解及讲练:1)“…, a mass campaign has been started to help solve it. “in the sentence above, “it” refers to_________2)研读第一段,完成“it”的词汇衔接链条: 词汇衔接: 指通过词汇选择在语篇中建立一贯穿语篇的链条,从而建立语篇的连续性。 sandstorms _____________ _________ it 3) “the four main places in the world ( where there are sandstorms) are central asia, north america, central africa and australia. ”括号中的句子是什么从句?( ) a. 地点状语从句 b.定语从句 c. 宾语从句 d.主语从句 4)“…traffic moves very slowly because the thick dust makes it difficult to see.” “traffic” means _____ a. 交通 b. 车辆 5) “already the government has planted more than 30 billion and plans to continue planting for the next five yeas.” “plans” 的词性是____ a. verb b.noun三、课内训练巩固:(一)听录音,课文缩写填空:sandstorms have been a major disaster for many asian countries for centuries. sandstorms are strong , dry winds. the wind is sometimes ______ _____ ______ move sand dunes. “___ ____ ____ ______ __ a sandstorm was a terrible experience,” ren jianbo said. desertification is a process that happens because people ____ ____trees and ____ ___ grass. traffic moves very slowly because the thick dust makes___difficult ____ ____. so weather experts _______ people _____ ____ go out . ___ prevent it _______nearer , the government is planting trees.(二)两人小组活动:以“沙尘暴”为话题采访talk about sandstorms in pairs, you can ask the following questions:what is a sandstorm?what are the causes of sandstormswhat should we do if sandstorms occur?how can we prevent sandstorms?四、课后作业:1.写一篇短文发到网上,指出沙尘暴的危害,呼吁人们保护环境。要求: 100字左右 2.找出课文中含不定式的句子答案二. 课堂学习研讨 1略读, 找出各段大意 para.1 –c para.2-a para.3 –b para.6-d para.5-f para.4-e 2查读:回答问题1.it is a strong, dry wind that carries sand2.she is wearing a mask to protect herself3.it moves very slowly because the thick dust make it difficult to see.4. stay at home.3细读: 填空归纳causesdesertificationclimate changes, cut down trees,dig up grasseffectsan orange sky, strong winds, move slowly,breathe, ilsuggestionsnot to go out , wear a mastmeasuresplant trees4研读:语篇理解及讲练:1) the problem2) a major disaster, the problem3) b 4) b 5) b三、课内训练巩固:strong enough to; to have been caught; cut down; dig up; it: to see; advise ; to coming共3页,当前第3页123