大学英语四级阅读理解练习十
Directions: There are 4 passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the centre.
Questions 1 to 5 are based on the following passage:
As the horizons of science have expanded, two main groups of scientists have emerged. One is the pure scientist; the other, the applied scientist.
The pure or theoretical scientist does original research in order to understand the basic laws of nature that govern our world. The applied scientist adapts this knowledge to practical problems. Neither is more important than the other, however, for the two groups are very much related.
Sometimes, however, the applied scientist finds the "problems" for the theoretical scientist to work on. Let's take a particular problem of the aircraft industry: heat-resistant metals. Many of the metals and alloys(合金)which perform satisfactorily in a car cannot be used in a jet-propelled plane. New alloys must be used, because the jet engine operates at a much higher temperature than automobile engine. The turbine wheel in a turbojet (涡轮喷气发动机)must withstand temperatures as high as 1 600 degrees Fahrenheit, so aircraft designers had to turn to the research metallurgist(冶金学家)for the development of metals and alloys that would do the job in jet-propelled planes.
Dividing scientists into two groups pure and applied is only one broad way of classifying them, however. When scientific knowledge was very limited, there was no need for men to specialize. Today, with the great body of scientific knowledge, scientists specialize in many different fields. Within each field, there are even further subdivisions. The various sciences have become more and more interrelated until no one branch is entirely independent of the others. Many new specialties-geophysics and biochemistry, for example-have resulted from combining the knowledge of two or more sciences.
1. Concerning the relative importance of pure and applied scientists, the writer thinks that ________.
A) applied scientists are more important
B) pure scientists are more important
C) neither are important
D) both are equally important
2. "The horizons of science have expanded" means that ________.
A) scientists can see further out into space
B) science has developed more fields of endeavor(事业)
C) the horizon changes size from year to year
D) scientists have made a machine for enlarging the horizon
3. The work of the pure scientist is __________.
A) working out laws for practical problems
B) developing materials to be applied to practice
C) doing original research to understand the nature of the universe
D) applying the basic laws to practical problems
4. New alloys must be found to ___________.
A) perform satisfactorily in a car
B) withstand high temperatures in jet-propelled planes
C) operate a jet-propelled plane
D) resist heat in a car
5. Different fields of science_________.
A) can be further divided.
B) are independent of the others.
C) are against the basic laws
D) have become less interrelated
Questions 6-10 are based on the following passage:
Thoughts from yesterday guide us toward tomorrow.
More than 2000 years ago, Caecilius Statius, a Roman slave who became famous as a playwright, observed, "We plant trees to benefit another generation." His remark is as apt (适当的) as it was when he made it and shows how thinkers of the past can still teach us something about the future.
George Bernard Show, for instance, made an even more perceptive remark. "We are made wise, not by the recollection(回忆)of our past, but by the responsibility for our future." This responsibility begins when we recognize that we ourselves create our future that the future is not something imposed upon us by fate or other forces beyond our control. We ourselves build the future both through what we do and what we do not do. Once we recognize our power over the future, we inevitably begin to anticipate the consequences of what we do and to do those things that will improve our future; in short, we begin to act wisely.
And our own responsibility for the future bears the promise of a better future world, because, as C. P. Snow, the novelist and philosopher, once remarked: "The sense of the future is behind all good policies. Unless we have it, we can give nothing either wise or decent to the world." And our obligations must be more to the future than the past. Our greatest responsibility is to be good ancestors.
6. According to the passage, the first sentence means ________.
A) we should often think about our past, which will make us a good man
B) should forget the past and get ready for the future
C) future is always promising than the past
D) we should use what we learnt in the past to build our future
7. What can we learn from Caecilius Statius' remark?
A) We should plant more trees than our descendants.(后代)
B) Tree will be a great help to our descendants.
C) We should do something useful (including planting trees) for another generation.
D) Tree is important to the world.
8. According to George Bernard Shaw, ______can make us wise.
A) what we learn in the past.
B) what we should do for the future
C) our memory of the past
D) our respect of the future
9. What does the sentence "our own responsibility for the future bears the promise of a better future world" mean?
A) Our own responsibility will build a better future world.
B) We bear the burden of our responsibility in the past.
C) We should make a promise to the next generation.
D) We should work hard.
10. According to the writer, what can we do for our descendants?
A) Anticipate the consequences of what we do
B) Protect the environment.
C)build the future
D)recognize our power over the future
Questions 11 to 15 are based on the following passage:
Criticism of research lays a significant foundation for future investigative work, but when students begin their own projects, they are likely to find that the standards of validity(效力)in field work are considerably stricter than the standards for most library research.
When students are faced with the concrete problem of proof by field demonstration, they usually discover that many of the important relationships they may have criticized other researcher for failing to demonstrate are very difficult to understand indeed. They will find, if they submit an outline or questionnaire to their classmates for criticism, that other students make comments similar to some they themselves may have made in discussing previously published research. For example，student researchers are likely to begin with a general question but find themselves forced to narrow its focus. They may learn that questions whose meanings seem perfectly obvious to them are not clearly understood by others, or that questions which seemed entirely objective to them appear to be highly biased (有偏见的) to someone else. They usually find that the formulation(准则) of good research questions is a much more subtle and frustrating task than is generally believed by those who have not actually attempted it.
11. What does the author think about trying to find weakness in other people's research?
A) It can be useful in planning future research.
B) It may cause researchers to avoid publishing good works.
C) It should only be attempted by experienced researchers.
D) It is currently being done to excess.
12.
12. According to the passage, what is one major criticism students often make of published research?
A) The researchers failed to provide an appropriate summary.
B) The researchers did not adequately establish the relationship involved.
C) The research has not been written in an interesting way.
D) The research has been done in unimportant fields.
13. How do students in class often react to another student's research?
A) They offer unusually good suggestions for improving the work.
B) They are especially critical of the quality of the research.
C) They react the way they do to any other researcher.
D) They show a lot of sympathy for the student researcher.
14. What do student researchers often learn when they discuss their work in class?
A) Some students feel that the conclusions are too obvious.
B) Other students rarely have objective comments about it.
C) Other students do not believe the researchers did the work themselves.
D) Some students do not understand the meaning of the researcher's questions.
15.Students may have to change their research projects because ________.
A) Their time is very limited
B) Their original questions are too broad
C) Their teachers do not give adequate abvice
D) Their budgets are too high
Questions 16 to 20 are based on the following passage:
Dry regions in the south western United States have become increasingly inviting playgrounds for the growing number of recreation seekers who own vehicles such as motorcycles or powered trail bikes and indulge (being crazy) in hill-climbing contests or in carving new trails in the desert. But recent scientific studies show that these off-road vehicles can cause damage to desert landscapes that has long-range effects on the area's water-conserving characteristics and on the entire ecology (the scientific study of the pattern of relations of plants, animals, and people to each other and to their surroundings), both plant and animal. Research by scientists in the western Mojave Desert in California revealed that the compaction (压实) of the sandy dry soil resulting from the passage of just one motorcycle markedly reduced the infiltration (渗透) ability of the soil and created a stream of rain runoff water that eroded the hillside surface. In addition, the researchers discovered that the soil compaction caused by the off-road vehicles often killed native plant species and resulted in the invasion of different plant species within a few years. The native perennial (多年生植物)(of a plant that lives for more than two years) species required many more years before they showed signs of returning. The scientists calculated that roughly a century would be required for the infiltration capacity of the Mojave soil to be restored after being compacted by vehicles.
16.What is the main topic of the passage?
A) Problems caused by recreational vehicle.
B) Types of off-road vehicles.
C) Plants of the southwestern desert.
D) The increasing number of recreation seekers.
17.According to the passage, what is being damaged?
A) Motorcycles.
B) The desert landscape.
C) Roads through the desert .
D) New plant species.
18.According to the passage, the damage to plants is ______________.
A) unnoticeable
B) superficial
C) long-lasting
D) temporary
19.According to the passage, what happens when the soil is compacted?
A) Little water flows through.
B) Better roads are made.
C) Water is conserved.
D) Deserts are expanded.
20.What is happening to the desert hillsides?
A) The topsoil is being eroded.
B) The surface is being watered.
C) There are fewer types of plants growing on them.
D) There are fewer streams running through them