As the result from the war, thousands of the Afghan people lost their lives. 查看更多

 

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British scientists are breeding a new generation of rice plants that will be able to grow. in soil con??taining salt water. Their work may enable abandoned farms to become productive farms once more.

Tim Flowers and Tony Yeo, from Sussex University’s School of Biological Sciences,. have spent several years researching how crops, such as rice, could be made to grow in water that has become salty. The pairs have recently begun a three-year programme, funded by the Biotechnology and Bio??logical Sciences Research Council, to establish which genes enable some plants to survive salty condi??tions. The aim is to breed this capability into crops, starting with rice.

It is estimated that each year more than 10 million hectares (公顷) of agricultural land are lost because salt gets into the soil and stunts(防碍生长) plants. The problem is caused by several factors. In the tropics, mangroves that create swamps (沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep (渗透) in. In Latin America, irrigation often causes problems when water is evaporated by the heat, leaving, salt deposits behind.

Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up the water they need to survive.

To overcome these problems. Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do not affect the plants’ growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resul??ting seeds are ready to be considered for commercial use.

Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food for the poorer countries of the world.

4. Which of the following statements about Flowers and Yeo is true?

A. They are students at Sussex University.  B. They are rice breeders.

5. Which of the following is NOT mentioned as a cause of the problem discussed in the passage?

A. Natural barriers to sea water have been destroyed.

B. The water table has gone down after droughts.

C. Sea level has been continuously rising.

D. Evaporation of water leaves salt behind.

6. The word "affect" in Paragraph 5 could be best replaced by________.

A. influence                B. effect                 C. stop                     D. present

7. The attitude of the author towards the research project is________.

A. positive                 B. negative             C. suspicious             D. indifferent

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完形填空。
     My husband and I both work at home. We have four children, so the times when I am   1   in the house
are few. Like many work-at-home moms, when I do get a   2   to be by myself, I fill that time with more    3  , whether it's related to my career or taking care of the housework. Most of the time, I don't mind.     4    , I wanted this job as wife and mother, and I knew from the start that it often     5   putting others'
needs before my own. But, other times, I can't help but feel a little    6   because I seldom had any plans for myself, and everyone knew it. My life     7    on my family, but they seldom appreciated this, which often   8   me a lot.
One day, when the kids were at school, I     9    for the movie theater-alone, I'd    10    been to the movies
alone before, so I was a little nervous. Would I look pitiful going to the theater by myself? Was I being
ridiculous (荒唐可笑) by seeing a movie     11    so much work waited for me at home? I    12    myself
to swallow these   13    and bought myself a ticket. And then I walked into the theater with my     14    held high and enjoyed every minute of the movie. I laughed and felt my good spirits     15    for a couple of hours, I was     16   wife or mother. I was just myself.
     From that point on, I     17    that Fridays would be mine,     18    for a couple of hours. Some Fridays,
I head to (前往) the beach with a good book. Other Fridays, I go shopping,     19    up a little fast food or
some clothes just for myself. I really   20     my Fridays after a long week of caring of my family.
(     )1. A. busy        
(     )2. A. chance      
(     )3. A. fun          
(     )4. A. So far      
(     )5. A. practiced    
(     )6. A. happy        
(     )7. A. centred      
(     )8. A. moved        
(     )9. A. applied      
(     )10. A. ever        
(     )11. A. if          
(     )12. A. forced      
(     )13. A. answers    
(     )14. A. hands      
(     )15. A. leave      
(     )16. A. everybody's
(     )17. A. expressed  
(     )18. A. at least    
(     )19. A. making      
(     )20. A. come up with
B. alone          
B. way            
B. fear          
B. From then on  
B. advised        
B. excited        
B. insisted      
B. bothered      
B. waited        
B. also          
B. when          
B. allowed        
B. efforts        
B. head          
B. happen        
B. somebody's    
B. declared      
B. at last        
B. picking        
B. break away from
C. tense          
C. purpose        
C. work            
C. As a resul      
C. meant          
C. angry          
C. depended        
C. amused          
C. longed          
C. never          
C. unless          
C. ordered        
C. thoughts        
C. legs            
C. return          
C. anybody's      
C. agreed          
C. in all          
C. taking          
C. look forward to
D. brave              
D. fortune            
D. love              
D. After all          
D. considered        
D. nervous            
D. knocked            
D. scared            
D. headed            
D. instead            
D. until              
D. taught            
D. results            
D. ticket            
D. weaken            
D. nobody's          
D. decided            
D. in time            
D. bringing          
D. pay attention to  

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The new model is the highly interactive(互动的)learning model. We could also call it the conversational model, or the tutorial model. It is computer based, with the interaction between the student, or a small group of students, and learning programs are like the conversation between a student and a skilled tutor. Distance learning will be the main delivery method.

Student interaction with the learning material on the computer will use the student's natural language; it will seem like a conversation between a student and a human tutor. This is the key point of highly interactive, or conversational, learning units. Programs will ask questions in the student’s native language, and respond reasonably to free-form student input. Multiple choice and pointing will seldom be used; they often do not allow individualization (个体化) of education.

An important aspect of this model is that the computer will frequently store information about the student, about problems and about how far individual students have progressed. These records will be used often within the programs. Thus when a student returns to the learning activity, the computer knows about that student and knows where to begin the new part.

Global education is critical for the future, to get rid of poverty, corruption (腐败), violence and war, to solve major problems such as the lack of drinkable water, and to insure a happy life for all. Education should no longer be limited to the wealthy of the world, but should be available to everyone.

In the new distance learning environment learning can take place in markets, libraries, public buildings, learning centers, and the home. Gradually schools and universities will play a smaller role in learning, both because better learning can be delivered through such highly interactive material, and because such learning will be less costly for the individual student. Motivation (动机)is particularly important in a mastery-based distance learning, as the usual threats of traditional classrooms such as that of low grades are no longer possible.

Voice input will probably be the mode(模式) for this interaction. The new voice input systems from several companies are useful, cheap, and speaker independent in highly interactive learning. Keyboards may not be needed. Speech is a natural way for humans to communicate.

Students will work in small peer groups, about four. Other contacts with people, learning circles, will be possible, directly or electronically.

68. What is not the new model also called?

A. interactive model       B. conversational model  

C. tutorial model          D. linguistic model

69. What does the model often use?

A. individualization of education            B. multiple choice and pointing

  C. questions in students’ native language      D. fixed-form student input

70. What do computers detect(检查) students about?

  A. Their future achievements      B. Their intelligences  

  C. Their problems               D. Their families

71. According to the passage, distance learning ____________ .

  A. is still expensive for ordinary students   

  B. will take place mainly in classrooms.

  C. will play a more important role in students’ learning.   

D. will still affect badly on the low-graded students

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When you want to go shopping, you’d better decide how much money you can spend on new clothes.

Think about the kind of clothes you really need. Then look for those clothes you really need. Then look for those clothes on sale.

There are labels(标签) inside all new clothes. The labels tell you how to take care of your clothes. The label for a shirt may tell you to wash it in warm water. A sweater label may tell you to wash in cold water. The label on a coat may say “dry clean only”, for washing may ruin this coat. If you do as the directions(说明) on the label, you can keep your clothes looking their best for a long time.

Many clothes today must be dry cleaned. Dry cleaning is expensive. When buying new clothes, check to see if they will need to be dry cleaned. You will save money if you buy clothes that can be washed.

You can save money if you buy clothes that are well done. Well-made clothes last longer. They look good even after they have been washed many times. Clothes that cost more money are not necessarily(不一定) better made. They do not always fit better. Sometimes less expensive clothes look and fit better than more expensive clothes.

The label inside the clothes tell you           

       A. how to keep them looking their best.

       B. how to save money.

     C. whether they fit you or not.

     D. where to get them dry cleaned.

If you want to save money, you had better buy clothes that__________.

A. don’t fit you                   B. don’t last long

     C. need to be dry cleaned           D. can be wash

We learn from the passage that cheaper clothes         

     A. are always worse made

     B. must be dry cleaned

     C. can not be washed

     D. can sometimes fit you better

Give the best title(标题)for this passage.

A. Buy Less Expensive Clothes   

B. Taking Enough Money When Shopping

C. Being a Clever Clothes Shopper            

D. Choosing the Label inside New Clothes

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     Apparently,we are safe neither at home nor in the business office.We use water in both places,but the research shows that chemicals added to our local water supply to kill harmful bacteria can have unwanted side effects.These chemicals can cause potential harm through drinking and in seemingly harmless activities as cleaning one’s house.They are released(set free)from water by daily actions like water running out of tap,spraying from garden pipes,or splashing in dishwashers and washing machines.As the water is moving.these chemicals are released into the air and then breathed in. Once inside our bodies, they start to affect our health.

  Does this mean we should stop bathing? No, say the scientists, but we should put all pollution into perspective. Activities at home such as the burning of coal, cooking oil, or even candles release carbon monoxide and particulates such as cigarette ashes which have been proven as harmful to health as working or living near heavy traffic. New tugs, bedding, and even clothing give off that“new smell, ”which is a sure sign of chemicals. In the office, newly applied paint, newly purchased telephones and other telecommunications equipment, and computers release polluting chemicals, too. As offices and homes often have inadequate ventilation (通风), these chemicals can build up to become health problems. Their poisonous effects are only now being slowly recognized.

  These facts suggest that, at a minimum, proper airing of newly purchased goods with an obvious chemical smell is a wise warning. Home and office windows should be opened during good weather. Even one’s car needs to be ventilated as well while in the garage.

  We need further research to understand better other potential health dangers, too. For example, the effects of overcrowding of schools (carbon dioxide build-up ), the factory work environment ( an endless list of potentially dangerous substances ), and even home heating and cooling (the air conditioner may be our enemies, not our friends) have only recently started to come to light. Until we understand the effects of our new technological environment better, we can only hope that“there is no place like home.”

What is the main idea of the first paragraph?

  A.The air we breathe in is harmful.

B.Chemicals are released in the running water.

C.Chemicals are added to the drinking water.

  D. The water in everyday use is unsafe.

.In Paragraph 2, the underlined sentence means that .

  A. homes and offices should be aired often

  B. any pollution should be taken into consideration

  C. bathing should be done with caution

  D.we should prevent any pollution from doing harm to us

What is the purpose of the passage?

  A.To call on us to guard our water.

  B.To show us that no place is like home.

  C.To make us aware of the pollution around us.

  D.To argue that neither homes nor offices are safe.

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