totally defenseless. It has a protection mechanism that defies belief. If temperatures get too hot, coral responds by trying to change the weather. It exudes an invisible chemical that floats above the water and encourages clouds to form, providing shade on the hottest days. It‘s an astounding mechanism, but it looks like it‘s being overwhelmed. Recently, the coral has been telling us that it‘s had enough, because when it overheats, it self-destructs, expelling the algae that live with them.
They turn deathly pale, a process known as bleaching. It‘s a desperate measure that will eventually kill them. So Ove is constantly monitoring the reef to see which corals are at risk. A temperature rise of just two degrees would wipe out almost all the coral on the Great Barrier Reef — a change that could happen within the next 60 years. No coral. No fish. No life.
And it‘s not the only effect of global warming. As carbon dioxide levels rise in the atmosphere, acidity levels rise in the ocean, dissolving the living coral away from the rocks. If it continues, the Great Barrier Reef will perish. We may be the last generation to see this incredible natural wonder as it is today. But the one thing that the past has taught us is that the reef always bounces back. The question is, will we be around to see it?
Home Listening ．．．．．．．．．．．．．
The study, from Stanford University in the United States, makes gloomy
assessments about the future health of the world‘s coral reefs. It finds that carbon
dioxide 1) __emissions_ are making seawater so acidic that coral reefs could begin to
disintegrate within a few 2)__decades_. The report states that even ambitious plans to stabilize greenhouse gas emissions, thought by many to be the main 3) ____cause__ of a warming climate, will not be enough to save the reefs. About a third of carbon emissions is soaked up by the world‘s oceans, where it 4) _combines__ with seawater to form carbonic acid.
The research comes as the Queensland state government in Australia 5) _announces__ a new plan to protect the Great Barrier Reef from 6) __agricultural pollution. The iconic reef is being damaged by pesticides and sediment from farms that seep into waterways. The Queensland government is to spend an 7) _extra_ $30,000,00 to reduce this hazardous run-off. Farmers also will face tougher 8)_environmental_regulations. Queensland Premier Anna Bligh says that man-made threats present serious challenges to the reef, which is a world heritage site.
Home Listening ．．．．．．．．．．．．．
Coral reefs are common in warm southern and equatorial oceans, and provide homes and feeding grounds for thousands of species, 9)
___including fish that are__important to the diets of millions of people in the developing world. In Asia, Indonesia and Papua
New Guinea are among the many countries that rely on reefs to provide food and to draw in tourists eager to explore the ocean. Environmental groups welcome the Queensland plan to protect the Great Barrier Reef. 10)_Farmers, however, argue that they have already taken significant steps to stop_the spread of pollutants from their lands
UNIT 5 ．．．．．Path to Leadership ．．．．．．．．．．．．．．．．
Lesson 1 Audio Script ．．．．．．．．．．．．．．．．．．Nelson Mandela, one of the world‘s most revered statesmen, led the struggle to replace the apartheid regime of South Africa with a multi-racial democracy. Jailed for 27 years, he emerged to become the country‘s first black president and to play a leading role in the drive for peace in other spheres of conflict. He won the Nobel Peace Prize in 1993. His charisma, self-depreciating sense of humor and lack of bitterness over his harsh treatment, as well as his amazing life story, partly explain his extraordinary global appeal.
Since stepping down as president in 1999, Mandela has become South Africa‘s highest-profile ambassador, campaigning against HIV/AIDS and securing his country‘s bid to host the 2010 football World Cup.
Mandela was also involved in peace negotiations in the Democratic Republic of Congo, Burundi and other African countries. He has also encouraged peace efforts in other areas of the world.
In 2004, at the age of 85, Mandela retired from public life to spend more time with his family and friends and engage in ―quiet reflection.‖
―Don‘t call me, I‘ll call you,‖ he warned anyone thinking of inviting him to future engagements. Lesson 1 Video Script ．．．．．．．．．．．．．．．．．． In the fall of 1979, Barack Obama said goodbye to his family and began his first year at Occidental. He became friends with several black students, but no matter how hard he tried he just didn‘t see himself as one of them.
―It was very important for him to figure out what it meant to be a part of the black community. He was an American. He was a black American. And he, I think, needed to figure out what that was.‖ At the end of his sophomore year, Obama transferred to Columbia University in New York. He hoped to find his place in the
city‘s diverse population. Once there, Obama took long walks through New York‘s ethnic neighborhoods. Obama became more disciplined. He ran three miles a day and studied harder. He also turned to books for answers about race and social injustice.
―He basically wasn‘t going out much. He was reading Nietzsche, and Gandhi, and absorbing just everything he could.‖
His work gained momentum, and he stopped using drugs.
―He was ready for a battle, and he was growing up. He had to figure out what he was going to do for the rest of his life.‖
Script ．．．．．． Obama stayed focused on his studies and began to think
about life after college. He eventually decided to pursue a career as a community organizer, where he hoped to confront the kind of racism and poverty that had troubled him for most of his life. After graduation, he took a job with a Chicago-based group called Developing Communities Project. He moved to the city‘s South Side and began working to improve the conditions in a public housing project called Alt-Geld Gardens.
Over the next few years, Obama succeeded at various projects, including school reform, hazardous waste cleanup and establishing a job training center.