一交流信息,走近龙卷风师:同学们,雪是一种自然现象,说说你还知道哪些自然现象。生:闪电、打雷、刮风、下雨。师:说到风,它的种类真不少呢,谁来说说?生:微风、大风、狂风、瑟瑟秋风。师:还有一种风,它来势狂暴凶猛,所过之处,面目全非。它是——(板书:龙卷风)关于龙卷风,大家有哪些了解?(生展示、交流收集的文字资料)生:龙卷风是一种相当猛烈的天气现象,由快速旋转并呈直立中空管状的气流形成。 An exchange of information, approached the tornado division: Students, snow is a natural phenomenon, talk about what you also know what natural phenomena. Health: lightning, thunder, windy, rainy. Teacher: When it comes to the wind, its type is really a lot of people, who say? Health: breeze, wind, wind, rustling autumn wind. Teacher: There is also a kind of wind, it comes furious violent, whereabouts, beyond recognition. (Tornado) What do we know about tornadoes? (生 生 示, 交 流 收集 的 资文 資料) Students: Tornadoes are a rather violent weather phenomenon formed by a rapidly rotating, .