A dam is a man-made structure built across a river. Most dams are built to control a river’s water flow, improve navigation and control flooding. However, some dams are built to produce hydro-electric power.

Hydro-electric power is produced as water passes through a dam, and into a river below. The more water that passes through a dam, the more energy is produced. Once a dam is built, a man-made lake is created behind the dam.

Electricity is produced by a kind of equipment called a turbine(水轮机). Turbines contain metal coils(线圈) surrounded by magnets(磁铁). When the magnets move round rapidly over the metal coils, electricity is produced. Turbines are located inside dams. The falling water makes the magnets go around the coils.

Dams provide clean energy, but they can also harm the environment. Species that use rivers to reproduce are often hurt by dams. In the Northwest of the US, the population of fishes has dropped from 16 million to 2.5 million since hydro-electric plants were built on the Columbia River. Dams all over the world have hurt some species. 

  The highest dam in the Unites States is located near Oroville, California. The Oroville Dam towers 230 meters and is more than a mile wide. This dam was built in 1968, 22 years after the Hoover Dam. The Hoover Dam, on the Nevada-Arizona border controls the Colorado river. It is 221 meters high and has 2.6 million hectare-meters of water.

The highest dam in the world is the Nurek Dam on the Vakhsh River in Tadzikistan, a country in central Asia. This dam is 300 meters tall. 

Which of the following statements is NOT true according to the passage?              

A. Some dams are built for controlling a river’s water flow.

B. Hydro-electric power is usually produced through a dam.

C. Dams can offer energy and they are harmless to the environment.

D. Generally speaking, where there is a dam, there is a man-made lake.

The third paragraph mainly tells us _____.                          

  A. how hydro-electric power is produced

  B. What a turbine is and how it works 

  C. how the magnets and the metal coils work

  D. how the falling water passes through a turbine                     

The dam which controls the Colorado river is ____.                  

A. the Oroville Dam  B. the Hoover Dam  C. the Nurek Dam  D. the Vakhsh Dam

A dam is a man-made structure built across a river. Most dams are built to control a river’s water flow, improve navigation and control flooding. However, some dams are built to produce hydro-electric power.

Hydro-electric power is produced as water passes through a dam, and into a river below. The more water that passes through a dam, the more energy is produced. Once a dam is built, a man-made lake is created behind the dam.

Electricity is produced by a kind of equipment called a turbine(水轮机). Turbines contain metal coils(线圈) surrounded by magnets(磁铁). When the magnets move round rapidly over the metal coils, electricity is produced. Turbines are located inside dams. The falling water makes the magnets go around the coils.

Dams provide clean energy, but they can also harm the environment. Species that use rivers to reproduce are often hurt by dams. In the Northwest of the US, the population of fishes has dropped from 16 million to 2.5 million since hydro-electric plants were built on the Columbia River. Dams all over the world have hurt some species. 

  The highest dam in the Unites States is located near Oroville, California. The Oroville Dam towers 230 meters and is more than a mile wide. This dam was built in 1968, 22 years after the Hoover Dam. The Hoover Dam, on the Nevada-Arizona border controls the Colorado river. It is 221 meters high and has 2.6 million hectare-meters of water.

The highest dam in the world is the Nurek Dam on the Vakhsh River in Tadzikistan, a country in central Asia. This dam is 300 meters tall. 

Which of the following statements is NOT true according to the passage?              

A. Some dams are built for controlling a river’s water flow.

B. Hydro-electric power is usually produced through a dam.

C. Dams can offer energy and they are harmless to the environment.

D. Generally speaking, where there is a dam, there is a man-made lake.

The third paragraph mainly tells us _____.       56-60 ADB                    

  A. how hydro-electric power is produced

  B. What a turbine is and how it works 

  C. how the magnets and the metal coils work

  D. how the falling water passes through a turbine                     

The dam which controls the Colorado river is ____.                  

A. the Oroville Dam  B. the Hoover Dam  C. the Nurek Dam  D. the Vakhsh Dam

On the border, a pack of wild dogs circled the soldiers for food． The leader of the pack was a gray- and-white dog called Nubs． He was   11  and hardly able to stand． Marine major Brian Dennis looked   12  and saw that there was a knife wound in his chest．
Dennis couldn't stand seeing the dog   13_．He and his men immediately treated the wound, and  gave Nubs medicine．Nubs pulled through but was still in   14 ．The next day, the team had to  15  . Ten days later, Dennis' unit was back, and so was Nubs． He was still   16 ，but the men fed him and  played with him．
Before long the unit once again left for the front 70 miles away． Nubs, slowly but 17  , followed them far into the trackless wasteland _ 18  the men lost sight of him．Two days later, beyond Dennis'   19  , he saw Nubs just outside the outpost（前哨）．The dog had  20  him across 70 miles of frozen desert to meet with the friend who had   21 his life．From then on Nubs and the men   22 in the same place, and ran around in the same ruins（废墟）．                          
Until an order came that they were not   23_ to have pets, Dennis decided to make sure the dog would  24 _ to live the good life．So he quickly raised $4,000 from his family and friends to 25 Nubs to America．
A year later, when Dennis and the dog were   26  in California, at first Nubs didn't   27  the guy．But within minutes, the dog jumped into Dennis' arms, jumping   28   again and again to lick his friend's face．
A little love and concern in the middle of   29 will not save a violent world． But small stories, like the story of a soldier and a clog, hold a  30  of a harmonious（和谐的）world．

A husband-and-wife team from California reached the Pacific Ocean after a 4,900- mile-cross
-country walk, becoming the first to backpack the American Discovery Trail in one continuous
walk. 
Marcia and Ken powers, of Pleasanton, started the travel across 13 states, through 14 national parks and 16 national forests on Feb. 27 from Cape Henlopen in Delaware. Nearly eight months later, the excited couple walked through water into the Pacific Ocean at Point Reyes, a day ahead of time. 
“We are a little sad that a great adventure is over. It was a fantastic adventure. And now we go home and just do housework. It's really sad.” Marcia, who said she's in her 50s, and her 60-year-old husband traversed cities, desert, mountains and farmland before reaching the Pacifics alone with arms around each other' s backpacks.
They overcame deep snow in the East, a quicksand in Utah, close lightning strikes in the Mid- west and strong desert sandstorms in the West while averaging 22 miles a day and taking only four days off. But they enjoyed the French history of St. Louis' the beauty of the Colorado Rockies and the kindness of strangers they met along the way. They particularly remember two brothers ---- a
doctor and dentist-------who put them up in their homes, after terrible days, and a motorcyclist who gave them water after they failed to find any on Utah's lonely Wah Wah Desert.
“Americans are truly warm-hearted and wonderful people.” Marcia Powers said. “We got to meet people that we would never meet in our daily living at home. We got to touch it with our feet and hands and smell all its scents and hear its wildlife. It' s an amazing country,” she added.
【小题1】Which of the following about couple's walk is TRUE?

D
At the railway stations all across Britain next week, groups of students will gather with their backpacks to wait for the trains that will carry them home for Christmas. This is a large movement of human beings as before, but with more contradictory traffic flows, so that trains filled with the young pass each other travelling in every direction.
At first, I went home every weekend with my washing, but then those visits became less regular. How did I let my parents know I was coming? They had no phone. Perhaps I wrote to them (“Expect me with dirty shirts this Friday afternoon”), but more likely I didn’t let them know, and just turned up or didn’t turn up, not understanding that my parents’ hopes of seeing me were a greater disappointment of my carelessness than a spoiled tea.
And in all this I suspect I was typical (有代表性的), at least of young men. As for our fathers and mothers, none of them talked of “empty-nest syndrome (综合症)”, even though its possible effect that the main human duty is to protect and feed the young would have suited their generation better than ours. Then, the feeling of loss went without a name. Today, it’s a condition with remedies, which will make parents feel more enjoyable in their life, The Mayo Clinic, for example, suggests you try to maintain regular contact with your children through “visits, phone calls, emails, texts or video chats”. If you feel unhappy, lean on (depend on … for support) loved ones or your mental health providers. Above all, stay positive: “Thinking about the extra time and energy that you might have to devote to your marriage or personal interests after your last child leaves home, it might help you adapt to this major life change.”
What can’t be denied, however, is that children often leave home. In modern societies, this is what they do. Christmas is the very time they can be depended on to return. For the non-religious, that may be this season’s true comfort and significance.
【小题1】The main reason for the busy traffic across Britain next week is that _______.