题目内容

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.

1.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.

2.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

3.The dam which controls the Colorado river is ____.

A. the Oroville Dam B. the Hoover Dam

C. the Nurek Dam D. the Vakhsh Dam

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Anyone who has ever played the game of Tetris (俄罗斯方块) knows the game’s surreal ability to spill into real life. After you shut off the game, you still see those Tetris blocks falling in your mind. You're grocery shopping and find yourself thinking about rearranging items on grocery shelves. Your mind continues to play the game, even when you're physically not.

Robert Stickgold, a Harvard professor, noticed something similar after a day hiking a mountain. That night, he dreamt he was still going through the motions of mountain hiking. Curious about this, he tried something: he got a group of college students of various skill levels to play Tetris and let them sleep in the Harvard sleep lab.

Over 60% of the students, including those who suffered from amnesia (健忘症), reported dreams of images of Tetris pieces falling, rotating (旋转), and fitting together. Interestingly, half the Tetris expert students reported such Tetris dreams, while 75% of the beginners did.

A study found that playing Tetris can grow your brain and make it more efficient. Adolescent girls played the game for an average of 1.5 hours a week over three months. The cerebral cortex (大脑皮层) of the girls grew thicker, while brain activity in other areas decreased. Richard Haier, who had found that there was a "Tetris learning effect", in which the brain consumed less energy as mastery of the game rose, concluded, "The brain is learning which areas not to use."

Haier's study showed that as the girls practiced playing the game, nerve cells made connections, communicating through synapses (a synapse is a connection between two nerve cells). When you learn something, you change those connections. Every time you reactivate(激活) a circuit, synaptic efficiency increases, and connections become more durable and easier to reactivate. Stickgold says sleep plays a role in this memory process.

So to sum up, whenever you do specific tasks over and over again, they take up less of your brain power over time. And that’s pretty amazing.

1.What does the underlined part ‘surreal ability’ in the first paragraph mean?

A. The game can help people arrange things in life.

B. The game can be applied to many aspects of life.

C. There are great similarities between the game and things in life.

D. The mind continues to play the game when we are doing other things.

2.What can we learn from Stickgold’s study?

A. More than half of the students dreamed of images of Tetris.

B. Students having bad memories didn’t dream of the game.

C. The Tetris expert students were more likely to dream of the game than the beginners.

D. More than half of the Tetris expert students didn’t dream of the game.

3.Playing Tetris for a long time can help ________.

①grow one’s brain

②one’s brain function efficiently

③arrange things tidily in life

④improve the adaptability of one’s brain

A. ①②③ B. ①②④

C. ②③④ D. ①③④

4.The purpose of the passage is to ________.

A. encourage people to play Tetris

B. warn people to focus while doing things

C. warn people not to play games before sleep

D. tell people they will improve at something if they keep doing it

I will have a holiday next week and I can’t decide what to do. I have a lot of work to do ___________ and this would be a good chance ___________. But I don’t like ___________ the holiday in such a way.I can work at home all the rest of the year.

Last year I went ___________ to the mountains. ___________ there was beautiful, but it is too cold this time of a year. And it’s really___________ far to go for a short holiday. I decide ___________ this isn’t a good time to___________the mountains.But I___________to go somewhere else.Perhaps this would be a good chance to go to the beach(海滨).I like to go for walks___________the seashore ___________the warm sunshine and watch the water. It’s only eight miles away and I could get there ___________about two hours. After thinking it___________,I am sure that this is a ___________time for the seashore than___________ .

Oh, here is a ___________ from Jim. He ___________ he is going to his house in the mountains for the___________,and he___________ me to go with him.___________ giving it some more thought, I wrote back to Jim and thanked him for that.

1.A. at home B. at house C. in school D. in factory

2.A. do it B. doing that C. to do it D. with that

3.A. to take B. to spend C. having D. asking

4.A. the north B. for north C. north D. to north

5.A. Nothing B. Everything C. Somebody D. Anything

6.A. very B. enough C. rather D. too

7.A. that B. what C. whether D. when

8.A. go B. go to C. go for D. leave

9.A. want B. wanted C. shall want D. was wanting

10.A. on B. by C. beside D. along

11.A. on B. during C. in D. under

12.A. in B. for C. with D. after

13.A. about B. of C. over D. on

14.A. good B. fine C. better D. best

15.A. home B. the mountains C. big cities D. country villages

16.A. gift B. call C. letter D. notice

17.A. says B. tells C. speaks D. talks

18.A. weekend B. holiday C. Sunday D. trip

19.A. want B. wish C. hopes D. asks

20.A. When B. With C. Without D. As

Want to find a job? Now read the following advertisements.
FAIRMONT HOTEL
Five waiters and Ten Waitresses
---Aged under 22
---At least high school graduate
---Good looking; men at least 1.72 meters tall and women 1.65
---Those knowing foreign languages preferred
---Paid 1600---2200 dollars per month
 One Secretary
---Aged under 30
---Female preferred
---Good at writing and skilled at computer
If interested, call 465-4768 or write to: Mr. Jack Hundris Room 0825, Fairmont Hotel
567 Wood Street, San Markers, 78003
Fax: 6954828
WILSON BOOKSTORE
Accountant(会计)
---Aged between 25 and 40
---With an experience of at least two years
---With a degree and an accountant certificate(证书)
---Paid 3000-4000 dollars monthly
---With a knowledge of computer
Salesclerk
---Basic education of 12 years or more
---Good at computer
---Paid 1800-2200 dollars monthly
Tel: 447-4398          Fax: 3485269

1.If you don’t know how to use a computer, you can just apply for the position as _________ .

A. a secretary

B. a waiter or a waitress

C. an accountant

D. a salesclerk

2.If you want to get the position of accountant in Wilson Bookstore, you have to satisfy the following conditions EXCEPT  _________ .

A. being a woman

B. knowing well how to use a computer

C. having been an accountant

D. having an accountant certificate

3.If you want to try for a job in Fairmont Hotel, you  _________ .

A. have to be a woman and know foreign languages

B. should be a university graduate

C. have to be taller than 1.72 meters

D. should be younger than 30 years old

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