人教版高中英语 必修三-Unit 4 Astronomy: the science of the stars Reading-课件（共14张PPT）

(共14张PPT)
Astronomy:
the science of the stars
Unit4
Guessing:
It looks like a ball but you can't play.
Everything can stand on it but never fall.
It is round but we usually think it is flat.
It moves anytime but no one feels.
What is it?
Reading:
How life began on the earth?
Fast reading:
What does the passage mainly talk about?
A.The importance of water.
B.The evolution(进化) process of life on the earth.
C.How human beings appeared.
D.How plants appeared.

(1)Why was it necessary for plants to grow
before animals?
A.Plants could protect animals from the sun.
B.Animals could hide from hunters in the forest.
C.Plants provided oxygen for animals to breathe.
D.It was easier for plants to grow.
Careful reading:

(2)How many years did dinosaurs exist
on the earth?
A.more than 65 million years
B.more than 65 billion years
C.more than 140 million years
D.more than 140 billion years

Careful reading:

(3)What does the “small clever animals” in
the last paragraph refer to?
A.mammals C. reptiles
B.Dinosaurs D. humans
Careful reading:

(4)What problem is caused by human beings?
A.They exist everywhere on the earth.
B.They cause global warming.
C.They find new methods of growing crops.
D.They enjoy hunting and fishing.
Careful reading:

Big Bang

A cloud of dust
A solid globe

Atmosphere
The earth

Water


Careful reading:
water

small water plants
shellfish & fish

green land plants
insects ＆amphibians


Careful reading:
reptiles
dinosaurs



forests
mammals
small clever animals

Careful reading:
Greenhouse effect


make the earth too hot
put too much carbon dioxide into the atmosphere
Discussion:
Some useful sentence structures for you:

It would be better if we can…
I'm going to…to help…
In order to protect the earth,we should…
Discussion:
solar energy
plant trees
recycle rubbish
save water