高中英语北师大版(2019)选择性必修第一册Unit 3 Conservation Lesson 1 The Sixth Extinction 课件 （29张PPT）

(共29张PPT)
Unit 3 Conservation
Lesson 1
The Sixth Extinction
目录页
contents
Pre-reading
I
Post-reading
IV
Fast Reading
II
Grammar
V
III
Intensive Reading
Ⅵ
Homework
Ⅰ
Pre-reading
How much do you know about extinction Search the Internet to find some background information and share it with your classmates.
Pre-reading
Ⅱ
Fast Reading
1. How many times up to today has life on Earth almost died out
2. About what percent of all specials on Earth became extinct during the mass extinction known as the “Great Dying”
3. What do scientists think will cause the nest mass extinction
Read and answer the questions.
Fast Reading
1. It is not common to see animals extinct in our planet. (　　)
2. The death of the dinosaurs occurred in the fourth mass extinction. (　　)
3. Species are dying out at an alarming rate. (　　)
4. Up to three-fourths of species will be extinct if there is a sixth mass extinction. (　　)
5. A sixth extinction is unavoidable. ( ) 　
F
F
T
T
F
Fast Reading: Exercise
Ⅲ
Intensive Reading
1. Which of the following is not included in the causes for the last five extinctions ( )
A. Global warming.
B. Volcanic eruptions.
C. The decrease of the oxygen content of the sea.
D. Human activity.
D
Intensive Reading
Read to choose the right answer.
2. Which of the following doesn’t belong to human activity ( )
Deforestation.
B. Air and water pollution.
C. Changes in sea levels.
D. Overfishing.
C
Intensive Reading
Read to choose the right answer.
3. What is the purpose of the last paragraph ( )
A. Appeal to people to protect the Earth.
B. Blame people for destroying the environment.
C. Urge the government to take action.
D. Warn the public to reduce their destructive behaviour.
A
Intensive Reading
Read to choose the right answer.
Read the plete the notes. Then talk about the different aspects of extinctions.
Intensive Reading
Meaning of extinction
__________________
__________________
The number of extinctions that have occurred so far
_____________________
_____________________
How to avoid the sixth mass extinction
________________
________________
Main reasons that cause extinctions
______________
______________
Two notable extinctions and their consequences
___________________
___________________
Extinction
Ⅳ
Post-reading
Up to now, there 1. __________ (be) five mass extinctions, where entire species are wiped 2. ______, among which the 3. ________　　　　　　(three) one is known as “Great Dying”. There are 4. _________ 　　　　　　(vary) reasons resulting in the extinction, 5. ___________ (range) from volcanic eruptions to 6. ________ (change) in sea levels.
has been
out
third
varied
ranging
changes
Read to fill in the blanks.
Post-reading
Many experts believe we are entering the sixth extinction and human activity is 7. ___________ (blame). The rate at 8. _______　　　　　　 animals are dying out 9. _________ (become) a cause for concern. We need to take steps to save endangered species and stop destroying 10. ______ planet where we live.
to blame
which
becomes
the
Read to fill in the blanks.
Post-reading
V
Grammar
Writing features
Writing methods
Adjectives
The
Sixth
Extinction
Writing style
Teaching focus
Verb phrases
Writing purpose
Word choices
Focus on grammar
Focus on writing features
Writing features
Writing methods
Writing style
Writing purpose
Focus on writing features
facts opinions / predictions reasons solutions
Use different colored pens to highlight at least one example for each of the four elements listed below.
1. In fact, over 90% of all species that ever lived are now extinct.
2. Many scientists say we are now entering the Earth’s sixth mass extinction.
fact
opinion
Focus on writing features
facts:
In the last 500 million years, there have been five times when
life on Earth has almost ended.
The “Great Dying” killed 90% to 96% of all species.
The fifth event, which occurred 66 million years ago, caused the death of the dinosaurs.
Human activity is causing species to die out 1, 000 times faster
than normal.
numbers
Focus on writing features
opinions / predictions:
Many scientists say we are now entering the Earth’s sixth mass extinction.
Scientists believe that up to three quarters of all
species on Earth could die out.
say, believe, think, in one’s opinion…
Focus on writing features
reasons:
There is a long list of reasons why so many species are dying out: air and water pollution, forests being destroyed, factory farming and overfishing.
Without forests, we would have no air to breathe and without clean water we would be unable to survive.
reason, as, without sth / sb, would…, cause, because, due to, since, for…
Focus on writing features
solutions:
We need to take steps to save endangered species, including setting up special areas where plants and
animals can be protected.
We need to change how we work and travel…
We also need to improve our farming methods.
need to do, should do…
Focus on writing features
numbers
facts
scientists /
experts say
reason, as…
we need to
solutions
reasons
opinions /
predictions
exposition
The
Sixth
Extinction
Focus on writing features
giving examples
For example, we need to take steps to save endangered
species, including setting up special areas where plants and
animals can be protected.
Focus on writing features
Writing methods
Writing purpose
citing ideas from experts or authorities
giving examples
using data
to explain what the sixth extinction is and its effects
to call on people to take action to prevent it from happening
Focus on writing features
Ⅵ
Homework
Homework
Choose two or three environmental problems that are caused by human activity. Offer solutions. Try to use relative clauses where appropriate.