1、必修 3Unit 4HOW LIFE BEGAN ON THE EARTHtheoryBig Bangatombillionglobeglobalviolentin timen. 学说；理论宇宙大爆炸；创世大爆炸n. 原子pron. & n. & adj. 万亿；十亿n. 球体；地球仪；地球adj. 全球性的；全世界的adj. 猛烈的；激烈的；强暴的及时；终于Words ReviewRead after the tape and speak out the Chinese immediately.carbondioxidecarbon dioxidenitrogenvapouratmosphe
2、reunlikefundamentalpresencen. 碳n. 二氧化物二氧化碳n. 氮 n.（ = vapor）蒸气；水蒸气n. 大气层；气氛prep. 与 不同；不像adj. 基本的；基础的n. 出席；到场；存在Words Reviewdissolveharmfulacidchainreactionmultiplyoxygenshellfishamphibianvt. & vi. 溶解；解散adj. 有害的n. 酸n. 链子；连锁；锁链n. 反应；回应 vi. & vt. 乘；增加n. 氧n. 水生有壳动物n. 两栖动物Words Reviewreptilelay eggsexistm
3、ammalgive birth tothusin ones turnprevent frompuzzlen. 爬行动物；爬虫下蛋vi. 存在；生存n. 哺乳动物产生；分娩adv. 因此；于是轮到某人阻止；制止n. 迷；难题vt.&vi. (使 )迷惑； (使 )为难Words Review1. To understand the passage about how life began on the earth2. To be able to give a brief introduction of the development of the Earth and the evolution
4、of life on the Earth3. To learn some words and expressions in the passage4. To arouse the students interest to explore the scienceRead the title and look at the pictures. Predict what the reading will be about.The Evolution of Life on the Earthtimeline古生代新生代中生代volcanic eruption(火山喷发 ) Now read the p
5、assage and get its main idea.Skimming for general ideaWhats the main idea of the text? A. A brief introduction on how human beings were born. B. A brief introduction on the birth of the universe and life on the earth. C. The “Big Bang” had a great effect on the birth of the earth. D. The appearance of human beings was a disaster to the earth. Choose the best answer.
