Exercise 9: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
In the twentieth - century, people depend on unlimited energy to power their everyday lives. A wide range of energy-run devices and modern conveniences are taken for granted, and although it may seem that we will never be in danger of living without those conveniences, the fact is that many supplies of energy are dwindling rapidly. Scientists are constantly searching for new sources of power to keep modern society running. Whether future populations will continue to enjoy the benefits of abundant energy will depend on the success of this search.
Coal, oil, and natural gas supply modern civilization with most of its power. However, not only are supplies of these fuels limited, but they are a major source of pollution. If the energy demands of the future are to be met without seriously harming the environment, existing alternative energy sources must be improved or further explored and developed. These include nuclear, water, solar, wind, and geothermal power, as well as energy from new, nonpolluting types of fuels. Each of these alternatives, however, has advantages and disadvantages.
Nuclear power plants efficiently produce large amounts of electricity without polluting the atmosphere; however, they are costly to build and maintain, and they pose the daunting problem of what to do with nuclear waste. Hydroelectric power is inexpensive and environmentally safe, but impractical for communities located far from moving water. Harnessing energy from tides and waves has similar drawbacks. Solar power holds great promise for the future but methods of collecting and concentrating sunlight are as yet inefficient, as are methods of harnessing wind power.
Every source of energy has its disadvantages. One way to minimize them is to use less energy. Conservation efforts coupled with renewable energy resources, such as a combination of solar, water, wind, and geothermal energy and alternative fuels, such as alcohol and hydrogen, will ensure supplies of clean, affordable energy for humanity's future.
It can be inferred from the passage that _______ .
A.many alternative energy sources are environmentally hazardous
B.solar and wind power are not promising for the future
C.most alternative energy sources have proven to be impractical
D.nuclear power solves one problem while creating others

Exercise 9: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
In the twentieth - century, people depend on unlimited energy to power their everyday lives. A wide range of energy-run devices and modern conveniences are taken for granted, and although it may seem that we will never be in danger of living without those conveniences, the fact is that many supplies of energy are dwindling rapidly. Scientists are constantly searching for new sources of power to keep modern society running. Whether future populations will continue to enjoy the benefits of abundant energy will depend on the success of this search.
Coal, oil, and natural gas supply modern civilization with most of its power. However, not only are supplies of these fuels limited, but they are a major source of pollution. If the energy demands of the future are to be met without seriously harming the environment, existing alternative energy sources must be improved or further explored and developed. These include nuclear, water, solar, wind, and geothermal power, as well as energy from new, nonpolluting types of fuels. Each of these alternatives, however, has advantages and disadvantages.
Nuclear power plants efficiently produce large amounts of electricity without polluting the atmosphere; however, they are costly to build and maintain, and they pose the daunting problem of what to do with nuclear waste. Hydroelectric power is inexpensive and environmentally safe, but impractical for communities located far from moving water. Harnessing energy from tides and waves has similar drawbacks. Solar power holds great promise for the future but methods of collecting and concentrating sunlight are as yet inefficient, as are methods of harnessing wind power.
Every source of energy has its disadvantages. One way to minimize them is to use less energy. Conservation efforts coupled with renewable energy resources, such as a combination of solar, water, wind, and geothermal energy and alternative fuels, such as alcohol and hydrogen, will ensure supplies of clean, affordable energy for humanity's future.
From the passage, it can be inferred that to solve our energy problems ________ .
A.a combination of conservation and invention will be needed
B.we will have to stop using many of our modern conveniences
C.scientists will have to find ways to increase our supplies of coal, oil, and gas
D.scientists will have to find one major source of nonpolluting energy

Exercise 9: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
In the twentieth - century, people depend on unlimited energy to power their everyday lives. A wide range of energy-run devices and modern conveniences are taken for granted, and although it may seem that we will never be in danger of living without those conveniences, the fact is that many supplies of energy are dwindling rapidly. Scientists are constantly searching for new sources of power to keep modern society running. Whether future populations will continue to enjoy the benefits of abundant energy will depend on the success of this search.
Coal, oil, and natural gas supply modern civilization with most of its power. However, not only are supplies of these fuels limited, but they are a major source of pollution. If the energy demands of the future are to be met without seriously harming the environment, existing alternative energy sources must be improved or further explored and developed. These include nuclear, water, solar, wind, and geothermal power, as well as energy from new, nonpolluting types of fuels. Each of these alternatives, however, has advantages and disadvantages.
Nuclear power plants efficiently produce large amounts of electricity without polluting the atmosphere; however, they are costly to build and maintain, and they pose the daunting problem of what to do with nuclear waste. Hydroelectric power is inexpensive and environmentally safe, but impractical for communities located far from moving water. Harnessing energy from tides and waves has similar drawbacks. Solar power holds great promise for the future but methods of collecting and concentrating sunlight are as yet inefficient, as are methods of harnessing wind power.
Every source of energy has its disadvantages. One way to minimize them is to use less energy. Conservation efforts coupled with renewable energy resources, such as a combination of solar, water, wind, and geothermal energy and alternative fuels, such as alcohol and hydrogen, will ensure supplies of clean, affordable energy for humanity's future.
Which of the following can be inferred from the passage?
A.Our present energy sources must be eliminated and replaced with alternative sources.
B.Demands for energy in the future are likely to decrease.
C.The search for alternative energy sources is not over.
D.Alternative sources of energy on this planet are very limited.

Exercise 9: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
In the twentieth - century, people depend on unlimited energy to power their everyday lives. A wide range of energy-run devices and modern conveniences are taken for granted, and although it may seem that we will never be in danger of living without those conveniences, the fact is that many supplies of energy are dwindling rapidly. Scientists are constantly searching for new sources of power to keep modern society running. Whether future populations will continue to enjoy the benefits of abundant energy will depend on the success of this search.
Coal, oil, and natural gas supply modern civilization with most of its power. However, not only are supplies of these fuels limited, but they are a major source of pollution. If the energy demands of the future are to be met without seriously harming the environment, existing alternative energy sources must be improved or further explored and developed. These include nuclear, water, solar, wind, and geothermal power, as well as energy from new, nonpolluting types of fuels. Each of these alternatives, however, has advantages and disadvantages.
Nuclear power plants efficiently produce large amounts of electricity without polluting the atmosphere; however, they are costly to build and maintain, and they pose the daunting problem of what to do with nuclear waste. Hydroelectric power is inexpensive and environmentally safe, but impractical for communities located far from moving water. Harnessing energy from tides and waves has similar drawbacks. Solar power holds great promise for the future but methods of collecting and concentrating sunlight are as yet inefficient, as are methods of harnessing wind power.
Every source of energy has its disadvantages. One way to minimize them is to use less energy. Conservation efforts coupled with renewable energy resources, such as a combination of solar, water, wind, and geothermal energy and alternative fuels, such as alcohol and hydrogen, will ensure supplies of clean, affordable energy for humanity's future.
The word "dwindling" in the first paragraph is closest in meaning to
A.diminishing
B.changing
C.increasing
D.limiting

Exercise 8: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions, many species became extinct at the same time- a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinction can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affecting even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intensive every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
What does the author say in paragraph 1 regarding most species in Earth's history?
A.They have been able to adapt to ecological changes.
B.They have caused rapid changes in the environment.
C.They have remained basically unchanged from their original forms.
D.They are no longer in existence.

Exercise 8: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions, many species became extinct at the same time- a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinction can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affecting even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intensive every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
The word "demise" in paragraph 2 is closest in meaning to _______ .
A.recovery
B.survival
C.death
D.change

Exercise 8: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions, many species became extinct at the same time- a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinction can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affecting even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intensive every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?
A.Availability of food sources
B.Temperature changes
C.Introduction of new species
D.Competition among species

Exercise 8: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions, many species became extinct at the same time- a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinction can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affecting even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intensive every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
The word "ultimately" in paragraph 1 is closest in meaning to
A.exceptionally
B.dramatically
C.unfortunately
D.eventually

Exercise 8: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions, many species became extinct at the same time- a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinction can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affecting even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intensive every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
In paragraph 3, the author makes which of the following statements about a species survival?
A.It reflects the interrelationship of many species.
B.It is associated with astronomical conditions.
C.It doesn't vary greatly from species to species.
D.It may depend on chance events.

Exercise 7: Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Peter lost the race because he ______ petrol on the last lap.
A.put out of
B.got out of
C.made out of
D.ran out of