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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 (公頃) of agricultural land are lost because salt gets into the soil and stunts(防礙生長) plants. The problem is caused by several factors. In the tropics, mangroves that create swamps (沼澤) 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 (滲透) 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

         Modcm inventions have speeded up people’s lives amazingly. Motor-cars cover a bundred miles in little more than an hour. Aireraft cross the world a day, while computers operate at lightning speed. Indeed, this love of speed seems never-ending. Every ycar motor-cars are produced which go even faster each new computer boasts（吹噓）of saving preeious seconds in handling tasks.

         All this saves timc, but at a prick.When we lose or gain half a day in speeding aeross the world in an airplane, our bodies tell us so. We get the uncomfoerable feeling known as jet-lag; our bodies feel tlru they have been left bebind in anot ar nine zoors Again pending too long at compulers resul’s in painti ninrts and fingers. Mobile phones also to dange according to some seientists; too much uss may thesmit h bul radiation into our brains, a we do not like to think about.

         Howave, what do we do with the time we have saved?Certainly not or so it seems. We are so accustomed to constant activity that we find it difficult to sit and do nothing, or even just one thing at a time. Pcrhaps the days are long gone when we might listen quietly to a story on the radio, letting imavination take us into another world.

         There was a time when some people’s lives were devotcd simply to the cultivation of the land or the eare of eattle. No multi-tasking there; their lives wenl on at a much gentler pace, and in a familiar pattern. There is much that we might envy about a way of life like this. Yet before we do so ,we must think of the hard tasks our ancestors faeed;:they farmed with bare hands, often lived close to hunger, and had to fashion tools from wood and stone. Modem machinery has freed peope fre that primitive existcnee.

1.The new rooucts opcome more and more time-saving beeause_________.

         A.our love of speed secure never-ending

         B.time is limited

         C.theprices are increasingly high

         D.the manufacturers boast a lot

2.What does“the days”in Paragraph 3 refer to?

         A.I maginary life               B.Simple life in the past

         C.Times of inventions           D.Time for constant activity

3.What is the author’s attitude towards the modem teehnology?

         A.Critical            B.Objective        C.Optimistic            D.Negative

4.What does the pa mge mainly diseuss?

         A.The present and past times             B.Machinary and human beings

         C.Imaginations and inventions            D.Modem technology and its influenec

Modcm inventions have speeded up people’s lives amazingly. Motor-cars cover a bundred miles in little more than an hour. Aireraft cross the world a day, while computers operate at lightning speed. Indeed, this love of speed seems never-ending. Every ycar motor-cars are produced which go even faster each new computer boasts（吹噓）of saving preeious seconds in handling tasks.
All this saves timc, but at a prick.When we lose or gain half a day in speeding aeross the world in an airplane, our bodies tell us so. We get the uncomfoerable feeling known as jet-lag; our bodies feel tlru they have been left bebind in anot ar nine zoors Again pending too long at compulers resul’s in painti ninrts and fingers. Mobile phones also to dange according to some seientists; too much uss may thesmit h bul radiation into our brains, a we do not like to think about.
Howave, what do we do with the time we have saved?Certainly not or so it seems. We are so accustomed to constant activity that we find it difficult to sit and do nothing, or even just one thing at a time. Pcrhaps the days are long gone when we might listen quietly to a story on the radio, letting imavination take us into another world.
There was a time when some people’s lives were devotcd simply to the cultivation of the land or the eare of eattle. No multi-tasking there; their lives wenl on at a much gentler pace, and in a familiar pattern. There is much that we might envy about a way of life like this. Yet before we do so ,we must think of the hard tasks our ancestors faeed;:they farmed with bare hands, often lived close to hunger, and had to fashion tools from wood and stone. Modem machinery has freed peope fre that primitive existcnee.
1.The new rooucts opcome more and more time-saving beeause_________.
A.our love of speed secure never-ending
B.time is limited
C.theprices are increasingly high
D.the manufacturers boast a lot
2.What does“the days”in Paragraph 3 refer to?
A.I maginary life               B.Simple life in the past
C.Times of inventions           D.Time for constant activity
3.What is the author’s attitude towards the modem teehnology?
A.Critical            B.Objective        C.Optimistic            D.Negative
4.What does the pa mge mainly diseuss?
A.The present and past times             B.Machinary and human beings
C.Imaginations and inventions            D.Modem technology and its influenec

         Modcm inventions have speeded up people’s lives amazingly. Motor-cars cover a bundred miles in little more than an hour. Aireraft cross the world a day, while computers operate at lightning speed. Indeed, this love of speed seems never-ending. Every ycar motor-cars are produced which go even faster each new computer boasts（吹噓）of saving preeious seconds in handling tasks.

         All this saves timc, but at a prick.When we lose or gain half a day in speeding aeross the world in an airplane, our bodies tell us so. We get the uncomfoerable feeling known as jet-lag; our bodies feel tlru they have been left bebind in anot ar nine zoors Again pending too long at compulers resul’s in painti ninrts and fingers. Mobile phones also to dange according to some seientists; too much uss may thesmit h bul radiation into our brains, a we do not like to think about.

         Howave, what do we do with the time we have saved?Certainly not or so it seems. We are so accustomed to constant activity that we find it difficult to sit and do nothing, or even just one thing at a time. Pcrhaps the days are long gone when we might listen quietly to a story on the radio, letting imavination take us into another world.

         There was a time when some people’s lives were devotcd simply to the cultivation of the land or the eare of eattle. No multi-tasking there; their lives wenl on at a much gentler pace, and in a familiar pattern. There is much that we might envy about a way of life like this. Yet before we do so ,we must think of the hard tasks our ancestors faeed;:they farmed with bare hands, often lived close to hunger, and had to fashion tools from wood and stone. Modem machinery has freed peope fre that primitive existcnee.

1.The new rooucts opcome more and more time-saving beeause_________.

         A.our love of speed secure never-ending

         B.time is limited

         C.theprices are increasingly high

         D.the manufacturers boast a lot

2.What does“the days”in Paragraph 3 refer to?

         A.I maginary life               B.Simple life in the past

         C.Times of inventions           D.Time for constant activity

3.What is the author’s attitude towards the modem teehnology?

         A.Critical            B.Objective        C.Optimistic            D.Negative

4.What does the pa mge mainly diseuss?

         A.The present and past times             B.Machinary and human beings

         C.Imaginations and inventions            D.Modem technology and its influenec

       Modcm inventions have speeded up people’s lives amazingly. Motor-cars cover a bundred miles in little more than an hour. Aireraft cross the world a day, while computers operate at lightning speed. Indeed, this love of speed seems never-ending. Every ycar motor-cars are produced which go even faster each new computer boasts（吹噓）of saving preeious seconds in handling tasks.

       All this saves timc, but at a prick.When we lose or gain half a day in speeding aeross the world in an airplane, our bodies tell us so. We get the uncomfoerable feeling known as jet-lag; our bodies feel tlru they have been left bebind in anot ar nine zoors Again pending too long at compulers resul’s in painti ninrts and fingers. Mobile phones also to dange according to some seientists; too much uss may thesmit h bul radiation into our brains, a we do not like to think about.

       Howave, what do we do with the time we have saved?Certainly not or so it seems. We are so accustomed to constant activity that we find it difficult to sit and do nothing, or even just one thing at a time. Pcrhaps the days are long gone when we might listen quietly to a story on the radio, letting imavination take us into another world.

       There was a time when some people’s lives were devotcd simply to the cultivation of the land or the eare of eattle. No multi-tasking there; their lives wenl on at a much gentler pace, and in a familiar pattern. There is much that we might envy about a way of life like this. Yet before we do so ,we must think of the hard tasks our ancestors faeed;:they farmed with bare hands, often lived close to hunger, and had to fashion tools from wood and stone. Modem machinery has freed peope fre that primitive existcnee.

1.The new rooucts opcome more and more time-saving beeause_________.

       A.our love of speed secure never-ending

       B.time is limited

       C.theprices are increasingly high

       D.the manufacturers boast a lot

2.What does“the days”in Paragraph 3 refer to?

       A.I maginary life               B.Simple life in the past

       C.Times of inventions           D.Time for constant activity

3.What is the author’s attitude towards the modem teehnology?

       A.Critical            B.Objective        C.Optimistic            D.Negative

4.What does the pa mge mainly diseuss?

       A.The present and past times             B.Machinary and human beings

       C.Imaginations and inventions            D.Modem technology and its influenec