How Life Began On The Earth导学案

师哈哈达人

高一英语必修三第四单元导学案

unit 4 asrtonomy: the science of the stars
第一课时 how life began on the earth
learning aims:
master the key words and expressions of the text.
read and understand the text—how life began on the earth
课前预习(resivion)：
preview new words and expressions:
words:
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
expressions:
1. to begin with               2. in time                  3. in one’ s turn                 
4. prevent...from              5. give birth to               
课堂阅读（procedures）：
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
paragraph 1:
paragraph 2:
paragraph 3:
paragraph 4:
paragraph 5:
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.共2页，当前第1页12

How Life Began On The Earth导学案
9 shellfish and other fish appeared.
10 the universe began with a “big bang”.
11 clever animals with hands and feet appeared.
12 mammals appeared.
task 3  post reading
fill in the blanks
finally about 2.6 million years ago some small ______ animals, now with hands and feet, appeared and _______ all over the earth. _____ they have, _______, become the most important animals on the planet. but they are not _____ the earth very well. they are putting too much _______ into the ______, which ______ heat _____ escaping from the earth into space. ____, many scientists believe the earth may become too hot to live on. so _______ life will continue on the earth for millions of years to come will ______ whether this problem can be solved.
讨论（discussion）
how can we protect the earth and make it a better place to live on?
家庭作业（homework）
read the text.
review the new words and expressions.
共2页，当前第2页12

How Life Began On The Earth导学案