研究生英语听说教程(基础级 第四版)答案 U12

Keys to Exercises
Unit T welve
Part Ⅰ Listening Practice
Section A Helping the Environment
Task 1
Person 1: smog
Person 2: plastic
Person 3: CFCs
Person 4: carbon dioxide/water shortage
Person 5: toxic chemicals
Person 6: deforestation
Task 2
Person 1: ride a bike
Person 2: use cloth bags when shopping
Person 3: use a car without an air conditioner
Person 4: plant trees and use as little water as possible
Person 5: avoid using chemical cleaners
Person 6: stop eating beef
Section B Earth Day Celebration
Task 3
1. Plant trees.
2. Learn more about the environment.
3. Reduce, reuse and recycle all day long.
4. Sing or listen to “Earth” songs.
5. Teach others about the environment.
6. Wear green or brown.
7. Cook a special Earth Day meal.
8. Ride your bike. 中国人民
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Task 4
Earth Day is a day of events and observances intended to inspire awareness of and appreciation for the Earth’s environment. Founded by United States Sena-tor Gaylord Nelson, this Earth Day is now observed on April 22 each year by more than 500 million people and several national governments in 175 countries.
Every day is Earth Day. Anything to help our environment is a perfect thing to do on Earth Day and every day. Don’t restrict yourself to just one day a year; learn about how you can make a difference to environmental protection all the time. And put it into practice – every day!
Section C Genetically Modified Food Task 5
Advantages
Disadvantages Crops could be made resistant to plant-killing chemicals.
There could be new toxins in foods.
Crops could be made resistant to bacteria, viruses, and insects.
Diseases could spread across different species of plants.More nutritious food could be developed.The ecological balance could be disturbed.
Plants could grow out of control. Section D Discussing the Environment 
Task 7
1. Issue being discussed:
The positive advances in technology vs. the damage it does to the environment.
2. Main points of each speaker:
Stevens: M odern innovations in technology cause irreversible damage to the en-
vironment.
Technological advances can’t keep up with negative impact. Grant: T echnology can reverse environmental damage.
Overpopulation can be limited by birth control.
Pollution can be cut down by effective means of mass transit.
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Keys to Exercises
Keys to Exercises
Task 8
Stevens thinks that technological innovation cannot solve the problems of environmental damage caused by technology itself, while Grant thinks that despite the damage caused by technology, there are many positive implications of technological innovation for environmental improvement.
Part Ⅲ　Listening Comprehension Test
Talk One
1. Reduce, reuse, recycle.
2. To reduce impulse buying.
3. B ecause they last long so they save you money and the environment in the long run.
4. R ecycling means collecting, processing, marketing, and ultimately reusing materials that were once discarded.
5. Glass, aluminum, steel, paper and cardboard, plastics.
Talk T wo
6. 85% and 70%.
7. 50%.
8. A system of megaparks (large national parks).
9. To protect the forests and help the environment.
10. P eople used to eat its eggs. Now they work in the tourist industry, including acting as guides to take tourists to see the turtles.
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