高考英语总复习 Unit 4 Astronomy the science of the stars教学案 新人教版必修3-新人教版高三必修3英语教学案

Unit 4 Astronomy: the science of the starsStep 1 课前准备——单元考点 自查自测1.词汇分层级识记过关 2.语境活用填写过关 3.经典句式背诵仿写过关 4.类词巧积累事半功倍(一)分门别类攻单词——识形辨意·拓展应用 (二)写用结合记短语——译写短语·语境活用(三)仿写活用练句式——经典句型·仿写背诵Step 2 课堂探究——核心考点 点点突破1.重点难点考点学通练透 2.归纳总结拓展开阔视野 3.方法规律技巧权威点拨 4.面面俱到打创高效课堂第一时段 Warming up & Reading1．harmful adj.有害的[教材原句] What many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas.很多科学家相信，由于地球上长期有水存在，使地球得以把有害气体和酸性物质溶解在海洋里。 (1)be harmful to 对……有害(2)harmless adj. 无害的(3)harm n. &vt. 伤害(4)cause/do harm to... 对……造成伤害/有害do harm to sb.＝do sb. harm 对某人有危害mean no harm 无恶意There is no harm in doing sth. 做某事没有害处单句语法填空①Some boys are too crazy about playing games on the computer, which is very ________(harm) to their health.②These days, breaking traffic rules and littering are not uncommon, causing serious harm __________ the environment.③If you want to solve the problem in this way, there is no harm ________ calling him.[答案] ① harmful ② to ③ in2．exist vi.存在；生存[教材原句] They laid eggs too and existed on the earth for more than 140 million years.它们也下蛋，在地球上生存了一亿四千多万年。(1)exist in 存在于……之中exist on 靠……为生There exists... 某地有……；存在……(2)existence n. 存在；生存come into existence 产生；成立；开始存在(3)existing adj. 现存的；现行的单句语法填空①The two sides have reached a partial agreement, but there is a difference still ________(exist) between them.②No one knows when such a custom first came into ________(exist)．③He finds it...