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共用题干
第三篇
Only special plants can survive in the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃.Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds which drive small-sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring.
Grasses and flowers in desert survive from one year to the next by existing through the long, hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.
Another factor that helps these plants to survive is the fact that their life cycles are short.By the time that the water from the spring rains disappears—ust a few weeks after it falls一such plants no longer need any.
The perennials（多年生植物）have special features which enable them to survive as plants for several years. Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in a short time.The small shoot system,on the other hand,considerably limits water loss by evaporation（蒸发）.
Another feature of many desert perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation during the dry season.Then,in the next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.
We can learn from the passage that the shoot system of the perennials_________.
A:can help the perennials absorb less of the sun's ray
B:decides the appearance of the perennials in desert
C:limits the function of the perennials' branches
D:may prevent the perennials from losing much water
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共用题干
Step Back in Time
Do you know that we live a lot longer now than the people who were born before us?One hundred years
ago the average woman lived to be 45.But now,she can live until at least 80.
One of the main reasons for people living longer is that we know how to look after ourselves better. We
know which foods are good for us and what we have to eat to make sure our bodies get all the healthy things
they need.We know why we sometimes get ill and what to do to get better again.And we know how impor-
tant it is to do lots of exercise to keep our hearts beating healthily.
But in order that we don't slip back into bad habits,let',have a look at what life was like 100 years
ago.
Families had between 15 and 20 children,although many babies didn'I live long. Children suffered
from lots of diseases,especially rickets（佝偻病）and scurvy（坏血病）,which are both caused by bad
diets.This is because many families were very poor and not able to feed their children well.
Really poor families who lived in crowded cities like London and Manchester often slept standing up,
bending over a piece of string,because there was no room for them to lie down.
People didn't have fridges until the 1920s.They kept fresh food cold by storing it on windowsills（窗台
板）,blocks of ice,or even burying it in the garden.
Some children had to start work at the age of seven or eight to earn money for their parents.if you had
lived 100 years ago,you might well be selling matchsticks（火柴杆）(a job done by many children) or
working with your dad by now.
Life was not easy for many children living 100 years ago.
A:Right
B:Wrong
C:Not mentioned
Step Back in Time
Do you know that we live a lot longer now than the people who were born before us?One hundred years
ago the average woman lived to be 45.But now,she can live until at least 80.
One of the main reasons for people living longer is that we know how to look after ourselves better. We
know which foods are good for us and what we have to eat to make sure our bodies get all the healthy things
they need.We know why we sometimes get ill and what to do to get better again.And we know how impor-
tant it is to do lots of exercise to keep our hearts beating healthily.
But in order that we don't slip back into bad habits,let',have a look at what life was like 100 years
ago.
Families had between 15 and 20 children,although many babies didn'I live long. Children suffered
from lots of diseases,especially rickets（佝偻病）and scurvy（坏血病）,which are both caused by bad
diets.This is because many families were very poor and not able to feed their children well.
Really poor families who lived in crowded cities like London and Manchester often slept standing up,
bending over a piece of string,because there was no room for them to lie down.
People didn't have fridges until the 1920s.They kept fresh food cold by storing it on windowsills（窗台
板）,blocks of ice,or even burying it in the garden.
Some children had to start work at the age of seven or eight to earn money for their parents.if you had
lived 100 years ago,you might well be selling matchsticks（火柴杆）(a job done by many children) or
working with your dad by now.
Life was not easy for many children living 100 years ago.
A:Right
B:Wrong
C:Not mentioned
The new service helped boost pre-tax profits by 10%.
A:return
B:increase
C:realize
D:double
A:return
B:increase
C:realize
D:double
共用题干
第二篇
The National Trust in Britain plays an increasingly important part in the preservation for public enjoyment of the best that is left unspoiled of the British countryside.Although the Trust has received practical and moral support from the Government,it is not rich Government department.It is a charity which depends for its existence on voluntary support from members of the public.
The attention of the public was first drawn to the dangers threatening the great old houses and castles of Britain by the death of Lord Lothian,who left his great seventeenth-century house to the Trust together with the 4,500-acre park and estate surrounding it. This gift attracted wide publicity and started the Trust's"Country House Scheme".Under this scheme,with the help of the Government and the general public,the Trust has been able to save and open to the public about one hundred and fifty of these old houses.Last year about one and three quarters of a million people paid to visit these historic houses,usually at a very small charge.
In addition to country houses and open spaces,the Trust now owns some examples of ancient wind and water mills,nature reserves,five hundred and forty farms and nearly two thousand five hundred cottages or small village houses,as well as some complete villages.In these villages no one is allowed to build,develop or disturb the old village environment in any way and all the houses are maintained in their original sixteenth-century style.Over four hundred thousand acres of coastline, woodland,and hill country are protected by the Trust and no development or disturbance of any kind are permitted.The public has free access to these areas and is only asked to respect the peace, beauty and wildlife.
So it is that over the past eighty years the Trust has become a big important organization and an essential and respected part of national life,preserving all that is of great natural beauty and of historical significance not only for future generations of Britons but also for the millions of tourists who each year invade Britain in search of a great historical and cultural heritage.
The word "invade" in the last paragraph is used to emphasize that________.
A:the British do not like tourists
B:tourists to Britain are friendly
C:tourists come to Britain in large numbers
D:Britain is attacked by masses of tourists
第二篇
The National Trust in Britain plays an increasingly important part in the preservation for public enjoyment of the best that is left unspoiled of the British countryside.Although the Trust has received practical and moral support from the Government,it is not rich Government department.It is a charity which depends for its existence on voluntary support from members of the public.
The attention of the public was first drawn to the dangers threatening the great old houses and castles of Britain by the death of Lord Lothian,who left his great seventeenth-century house to the Trust together with the 4,500-acre park and estate surrounding it. This gift attracted wide publicity and started the Trust's"Country House Scheme".Under this scheme,with the help of the Government and the general public,the Trust has been able to save and open to the public about one hundred and fifty of these old houses.Last year about one and three quarters of a million people paid to visit these historic houses,usually at a very small charge.
In addition to country houses and open spaces,the Trust now owns some examples of ancient wind and water mills,nature reserves,five hundred and forty farms and nearly two thousand five hundred cottages or small village houses,as well as some complete villages.In these villages no one is allowed to build,develop or disturb the old village environment in any way and all the houses are maintained in their original sixteenth-century style.Over four hundred thousand acres of coastline, woodland,and hill country are protected by the Trust and no development or disturbance of any kind are permitted.The public has free access to these areas and is only asked to respect the peace, beauty and wildlife.
So it is that over the past eighty years the Trust has become a big important organization and an essential and respected part of national life,preserving all that is of great natural beauty and of historical significance not only for future generations of Britons but also for the millions of tourists who each year invade Britain in search of a great historical and cultural heritage.
The word "invade" in the last paragraph is used to emphasize that________.
A:the British do not like tourists
B:tourists to Britain are friendly
C:tourists come to Britain in large numbers
D:Britain is attacked by masses of tourists
Everybody was gald to see Mary back.
A:sorry
B:sad
C:angry
D:happy
A:sorry
B:sad
C:angry
D:happy
共用题干
第一篇
U. S. Blacks Hard-hit by Cancer
Death rates for cancer are falling for all Americans,but black Americans are still more
likely to die of cancer than whites,the American Cancer Society said Monday.
In a special report on cancer and blacks,the organization said blacks are usually
diagnosed with cancer later than whites,and they are more likely to die of the disease.
This could be because of unequal（不平等的）access to medical care, because blacks
are more likely to have other diseases as well,and perhaps because of differences in the
biology（生物学）of the cancer itself, the report added.
"In general,black Americans have less hope of surviving five years after diagnosis
than whites for all cancer sites and all stages of diagnosis,"the report said,
"In describing cancer statistics for black Americans,this report recognizes that many of
the differences associated with race may be caused by unfair social and economic
differences and unequal access to medical care."
The cancer society said blacks should be encouraged to get check-ups（体格检查）
earlier,when cancer is more treatable,and it said more research is needed to see if
biological differences play a role.
"The new statistics emphasize the continuing importance of wiping out these unfair
social differences through public policy and education efforts,"the organization said in a
statement.
But it also noted a drop in cancer death rates.
"Cancer death rates in both sexes for all sites combined have dropped greatly among
black Americans since 1992,as have incidence rates（发生率）,"said the report.
Cancer is more treatable if it is detected
A:in an early stage.
B:in a late stage.
C:all of a sudden.
D:together with other diseases.
第一篇
U. S. Blacks Hard-hit by Cancer
Death rates for cancer are falling for all Americans,but black Americans are still more
likely to die of cancer than whites,the American Cancer Society said Monday.
In a special report on cancer and blacks,the organization said blacks are usually
diagnosed with cancer later than whites,and they are more likely to die of the disease.
This could be because of unequal（不平等的）access to medical care, because blacks
are more likely to have other diseases as well,and perhaps because of differences in the
biology（生物学）of the cancer itself, the report added.
"In general,black Americans have less hope of surviving five years after diagnosis
than whites for all cancer sites and all stages of diagnosis,"the report said,
"In describing cancer statistics for black Americans,this report recognizes that many of
the differences associated with race may be caused by unfair social and economic
differences and unequal access to medical care."
The cancer society said blacks should be encouraged to get check-ups（体格检查）
earlier,when cancer is more treatable,and it said more research is needed to see if
biological differences play a role.
"The new statistics emphasize the continuing importance of wiping out these unfair
social differences through public policy and education efforts,"the organization said in a
statement.
But it also noted a drop in cancer death rates.
"Cancer death rates in both sexes for all sites combined have dropped greatly among
black Americans since 1992,as have incidence rates（发生率）,"said the report.
Cancer is more treatable if it is detected
A:in an early stage.
B:in a late stage.
C:all of a sudden.
D:together with other diseases.
