文档介绍：Unit 4
Astronomy：
the science of the stars
1
完整最新版课件
Uranus 天王星
Venus 金星
Earth 地球
Mars 火星
Mercury 水星
Neptune 海王星
Saturn 土星
Jupiter 木星
Quiz:
In our solar system eight planets circle around the Sun. What are they? Match the names with the planets.
2
完整最新版课件
Fast reading
Read the passage quickly and find the main idea.
A brief introduction on how the universe developed and how life began on the earth.
3
完整最新版课件
Careful reading
Para 1:
Para 2:
Para 3:
Para 4:
Para 5:
A widely accepted theory about the formation of the universe.
The formation of the earth.
The importance of water for life.
The development of plants and animals on the earth.
The arrival of humans and their impact on the earth.
Read the passage carefully and analyse its structure.
earth, atmosphere and water
life development
human beings
4
完整最新版课件
1. What is the original earth’s atmosphere made up of?
2. Why did scientists believe water is fundamental to the development of life?
3. How did water come into being on the earth?
4. Which kind of life-being first appeared on the earth, plants or animals? Why?
5. Why were mammals different from all life forms in the past?
Answer the following questions.
5
完整最新版课件
Carbon, nitrogen, water vapour, and other gases.
2. Why did scientist believe water is fundamental to
the development of life?
Because water allowed the earth to dissolve harmful gases and acids into the oceans and seas to ensure a following chain reaction, which made it possible for life to develop.
What is the original earth’s atmosphere made up
of?
3. How did water come into being on the earth?
The explosion of the earth produced water vapor, which turned into water when the earth cooled down.
6
完整最新版课件
4. Which kind of life-being first appeared on the
earth, plants or animals? Why?
At first, small plants began to appear on the surface of the water, they produce oxygen, which encouraged the late