Unit3 Conversation L1 The Sixth Extinction 课件 --2025-2026学年高中《英语 选修1》（北师大版）

endangered extinctendangered extinctThe Sixth ExtinctionAccording to the title, what will possibly be talked about in the passage?Extinctions, where entire species are wiped out, are not unusual in our Earth’s history. In fact, over 90 percent of all species that ever lived are now extinct. In the last 500 million years, there have been five times when life on Earth has almost ended. These include the third mass extinction, known as the “Great Dying”, which killed 90% to 96% of all species. And the fifth event, which occurred 66 million years ago, caused the death of the dinosaurs. The reasons for extinctions are varied. According to scientists, they include volcanic eruptions, asteroids hitting the Earth from space, changes in sea levels, the decrease of the oxygen content of the sea and global warming. Many scientists say we are now entering the Earth’s sixth mass extinction. This time, human activity will be to blame.Para 1Para 2 Although it is not unusual for species to die out naturally, the rate at which this is now happening is cause for concern. A 2015 study by scientists who were based at Brown University and Duke University in the US, looked at how quickly species die out due to natural causes, that is, the “background extinction rate”. They found that human activity is causing species to die out 1,000 times faster than normal. 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. It is clear that human activity has negatively affected all other species on Earth, including animals and plants. If a sixth mass extinction occurs, scientists who have studied the issue believe that up to three quarters of all species on Earth could die out. Of course, as we humans depend on so many species for our survival, we would also be at risk of dying out. Our world and our lives depend on the balance in nature between animals and plants. Without forests, we would have no air to breathe, and without clean water we would be unable to survive. Para 3humansanimalsplantsCan a sixth extinction be avoided? Experts say that it is not yet too late, if we take action now. This would mean we have to significantly change the way we live. For example, 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 by using cleaner, more natural sources of energy, such as wind and solar energy. We also need to improve our farming methods to reduce water, air and land pollution. In short, if we want to survive, we need to stop destroying the planet that we live on and start to protect it.Para 4 Use one or two words to summarize what each paragraph talks about.What is the case study mainly about? 1. What is the writing purpose of the whole passage?1. What is the writing purpose of the whole text?2. What is the text type?narration (记叙文）argumentation (议论文） exposition (说明文）3. What is the writer’s attitude towards the sixth extinction? Positive or negative? Why?Are we now entering the sixth extinction?1.Use your experience, life observations and knowledge to show how human activities are affecting the environment.2. Think of any effective measures that you can take in real life to help solve the environmental problems.Research online and find more information to support your idea. Polish your language.Option 1: Write an essay. Option 2: Make a video.Are we now entering the sixth extinction?Thank you !