How Life Began On The Earth导学案
unit 4 asrtonomy: the science of the stars
第一课时 how life began on the earth
master the key words and expressions of the text.
read and understand the text—how life began on the earth
preview new words and expressions:
1. violent adj.强暴的，猛烈的violence n.暴力，强暴；猛烈 violently adv. 强暴地；猛烈地
2. fundamental adj.基本(础)的n.[pl.]基本原则(法则) fundamentally adv. 基本地；根本地
3. development n.生长，发展；新情况 develop vt.发展；产生vi.生长；发展
developed adj. 发达的developing adj. 发展的
4. lay vt.放下；摆设；产(蛋) lay-laid-laid-laying lie vi. 躺，平放；位于lie-lay-lain-lying lie n.&vi. 谎话；说谎 lie-lied-lied-lying
5. prevent vt. 预防，防止 prevention n.预防；阻止；妨碍 preventable adj.可防止的，可预防的
1. to begin with 2. in time 3. in one’ s turn
4. prevent...from 5. give birth to
task 1: fast reading
skim the passage and find out the main idea of the text.
the main idea
task 2: careful reading
1. analyse the structure of the passage. write down the main idea for each paragraph
2.answer the following questions:
(1) after the big bang, what happened?
(2) what happened next?
(3) what did the water vapour and gases form?
(4) what appeared on the earth then?
(5) what did the water do?
3.put the order of development of life into a timeline. use the reading passage to help you.
(1) insects and amphibians appeared.
(2) dinosaurs appeared.
(3) the earth became a solid ball.
(4) small plants grew on the water.
(5) reptiles appeared.
(6) plants began to grow on dry land.
7 the earth was a cloud of dust.
8 water appeared on the earth.