(共23张PPT)
Reading Unit 4 Astronomy
What is the text about according to the title?
How life began on the earth.
How?
a cloud of dust
globe
violent surface
atmosphere
dinosaur
reptile
amphibian
mammals
acid rain
a cloud of dust
globe
Big Bang
violent surface
water
atmosphere
dinosaur
early plants
reptile
atom
fish
insect
amphibian
man
mammals
acid rain
eggs
pollution
1
2
3
4
5
6
7
8
10
11
12
13
14
15
16
17
18
9
Put the order of development of life into a time line.
Insects and amphibians appeared.
Dinosaurs appeared.
The earth became a solid ball.
Small plants grew on the water.
Reptiles appeared .
Plants began to grow on dry land.
The earth was a cloud of dust.
Water appeared on the earth.
Shellfish and other fish appeared.
The universe began with a “Big Bang”.
Clever animals with hands and feet appeared.
Mammals appeared.
10
7
3
8
4
9
6
1
5
2
12
11
What does each paragraph mainly tell us?
the universe
the earth
water
plants and animals
humans
Para 1 A widely accepted theory about the formation of the universe
Para 2 The formation of the earth
Para 3 The importance of water for life
Para 4 The development of plants and animals
on the earth
Para 5 The arrival of humans and their effects on the earth
Para.1
The universe began with a “Big Bang” that threw matter in all directions.
Para.2 : How did the earth come into being?
The earth’s
atmosphere
nitrogen
…
…
carbon
water
vapour
Para 3.
Why was water important for the beginning of life on the earth?
Because it allowed the earth to dissolve harmful gases and acids into the oceans and seas. This produced a chain reaction, which made it possible for life to develop.
Para. 4 : Find out the lives from this part.
4 land animals
Next
In some films and stories, we can see dinosaurs and people together. Is it right? Why?
Because dinosaurs died out long before human beings developed on the earth.
human beings
Para.5
A cloud of dust → a solid ball → presence of water → on the water → shellfish & other fish → plants begin to grow on dry land → insects and amphibians appear → retiles appear → dinosaurs appear → mammals appear
The development of life
insects and amphibians appear
reptiles appear
dinosaurs appear
mammals appear
True (T) or False (F).
1. The earth appeared before the Big Bang happened.
2. The original atmosphere consisted of nitrogen and oxygen.
3. Life began in water and then on land.
F
F
T
4. Dinosaurs could give birth to young baby animals and produced milk to feed them.
5. Human beings produce too much carbon dioxide which causes the global warming on the earth.
F
T
People are putting too much carbon dioxide into the atmosphere, which prevents heat from escaping from the earth into space.
The earth may become too hot for the lives on it.
global warming
ice in the North Pole______
water level ______
The result is that …
rises
melts
After reading
How life began on the earth
“Big Bang”
other bodies
________
stars
Earth: a cloud of _____
atoms
dust
a solid _____
the earth’s _____________
other 4.
_____
Water: ____________ to the development of life
water vapour
nitrogen
carbon
extremely small _______ on the
surface of the water
globe
gases
atmosphere
fundamental
plants
early _________ and all sorts of fish
green plants on land
land animals
insects
amphibians
___________
huge animals
(dinosaurs)
the rise of __________
human beings
shellfish
reptiles
mammals