Unit3ConservationLesson1TheSixthExtinction课件高二英语北师

3. What is the type of this article?
A. Narration (记叙文).
B. Argumentative Essay (议论文).
√C. Expository Writing (说明文).
D. News Report (新闻报道).
4. Check your answers to the activity in Pre-reading.
It is clear that human activity has negatively affected all other species on Earth, including animals and plants.
Para. 3
1. What would happen if a sixth mass extinction occurs?
3. Paraphrase the following sentence. Many scientists say we are now entering the Earth’s sixth mass extinction. This time, human activity will be to blame. Many scientists hold the idea that we are about to go through the sixth extinction which human activity should be responsible for.
context; 4.To express solutions to environmental problems.
Pre-reading
1. What does the word “Extinction” mean? Extinction is a situation in which something no longer exists on our planet.
2. What is the main idea of the passage? __E_x_ti_n_c_ti_o_n_s_ are not unusual in our Earth’s history. But we humans can t_a_k_e_a_c_ti_o_n_ to stop destroying the planet we live on to avoid__a__si_x_th__e_x_ti_n_c_ti_o_n____.
(4) Main reasons that cause extinctions_____________ ______________________
(3) Two notable extinctions and their consequences _______________________ ___________________
A. Less than 10%. B. Nearly 50%. C. More than 90%.
3. What do scientist think will cause the next mass extinction?
A. Human activity. B. Natural causes. C. Unknown reasons.
Para. 2 1. What did scientists find out in 2015? They found that human activity is causing species to die out 1,000 times faster than normal.
2. What are the reasons why so many species are dying out? The reasons are varied, such as air and water pollution, forests being destroyed, factory farming and overfishing.
3. Which sentence in this paragraph can replace the following one? What is obvious is that our human activity has had a negative influence on all other species on Earth, such as animals and plants.
How much do you know about extinction? Choose the option based on your knowledge.
1. How many times up to today has life on Earth almost died out?
A. Once.
(3) Two notable extinctions and their consequences:
• The __th_i_rd___ mass extinction, known as the “Great Dying”, which killed _9_0_%___to__9_6_%___of all species. • The _f_i_ft_h__ event, which occurred 66 million years ago, caused the death of the __d_i_n_o_s_au_r_s__.
Para. 1 1.Read the first paragraph and complete the notes.
(1) Meaning of extinction _____________________ _______f extinctions that have occurred so far __________
▲Up to _t_h_re_e__q_u_a_rt_e_rs__of all species on Earth could die out. ▲Humans would also be _a_t_r_i_sk__o_f_ dying out, because our world and lives depend on _t_h_e_b_a_l_a_n_c_e_ in nature.
√ A. Less than 10%. B. Nearly 50%. C. More than 90%.
3. What do scientist think will cause the next mass extinction?
√A. Human activity. B. Natural causes. C. Unknown reasons.
(4) Main reasons that cause extinctions
• _V_o_l_c_an_i_c_e_r_u_p_ti_o_n_s_. • Asteroids hitting the Earth from space • Changes in sea levels. • The decrease of the oxygen content of the sea. • __G_l_o_b_a_l _w_a_r_m_i_n_g__.
In the past 500 million years, there have been_f_iv_e__ti_m_e_s__ extinctions, in which o_v_e_r_9_0_%__o_f__al_l_s_p_e_c_ie_s_ that ever lived are now extinct.
(1) Meaning of extinction
(2) The number of extinctions that have occurred so far
Extinctions are__w_h_e_r_e__ entire species are wiped out, _w_h_i_c_h_ are not unusual in our Earth’s history.
√B. Five times. C. More than 10 times.
2.About what percent of all species on Earth became extinct during the
mass extinction known as the “Great Dying”?
2. How much do you know about extinction? Choose the option based on your knowledge.
1. How many times up to today has life on Earth almost died out?
A. Once.
3. Paraphrase the following sentence. Without forests, we would have no air to breathe, and without clean water we would be unable to survive. If there were no forests, we would not breathe；if there were no clean water, we would die.
Para. 4
1. What is the purpose of the last paragraph?
√A.Call on 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.
Lesson 1 The Sixth Extinction
UNIT 3 CONSERVATION
1.To read and talk about conservation; 2.To read for general understanding; 3.To read for specific information and understanding words in the
B. Five times. C. More than 10 times.
2.About what percent of all species on Earth became extinct during the
mass extinction known as the “Great Dying”?
While-reading
1. Read the passage quickly and match the main idea with each paragraph.
Para.1 A. Human activity causes species to die out faster. Para.2 B. How do we avoid a sixth mass extinction? Para.3 C. Extinctions in history and the reasons. Para.4 D. The possible consequences of the sixth mass extinction.
2. Which writing method is NOT used in this paragraph? A.Giving data. B.Analyzing cause and effect. C.Making comparison.
√D.Arranging in the time order.