必修三UnireadingPPT课件

Early shellfish and all sorts of fish
Some animals (ampபைடு நூலகம்ibian & insects) came to land.
Reptile appeared.
dinosaurs
mammals
Man had evolved from apes.
Unit 4
Astronomy： the science of the stars
Neptune 海王星 Uranus 天王星 Saturn 土星 Jupiter 木星 Mars 火星 Earth 地球
Quiz:
Venus 金星 Mercury 水星
In our solar system eight planets circle around the Sun. What are they? Match the names with the planets.
Read the passage carefully and analyse its structure.
Para 1:Aewaridtehly, aatcmcepotsepdhthereoeraynabdowutattheer
formation of the universe. Para 2:The formation of the earth.
Let review the evolution of life on the earth.
After the “Big Bang”, the earth was full of water.
Original cells appeared in the ocean.
The cells in the water began to separate. Small plants came into being.
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
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.
Careful reading
Discussion
We are making the world better.
We are making the world worse.
Because they are putting too much carbon dioxide into the atmosphere.
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.
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 later development of early shellfish and all sorts of fish.
on the earth.
Answer the following questions.
1. What is the original earth’s atmosphere made up of? 2. Why did scientists believe water is fundamental to the
the past?
1. What is the original earth’s atmosphere made up of? 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.
Para 3:Thleifiempdoertvaencloe opfmwaetnertfor life.
Para 4:The development of plants and animals on the earth.
Para 5: Thhuemararnivabl eoifnhgusmans and their impact
5. Why were mammals different from all life forms in the past?
They were different because they produced their young from within their bodies and produce milk to feed them.