The scientist was so absorbed in his work that he was not ______ of the fire that was spre
A.adequate
B.alive
C.aware
D.awake
A.adequate
B.alive
C.aware
D.awake
21. A.relax
B.went down
C.fear
D.themselves
E. with
22. A.relax
B.went down
C.fear
D.themselves
E. with
23. A. relax
B. went down
C. fear
D. themselves
E. with
24. A.relax
B. went down
C. fear
D. themselves
E. with
25.A. relax
B. went down
C. fear
D. themselves
E. with
Aluminum is lightweight, rustproof and easily shaped into different forms. By mixing it with other metals, scientist have been able to produce a variety of alloys, some of which have the strength of steel but weigh only one third as much.
Today, the uses of aluminum are innumerable. Perhaps its most important use is in transportation. Aluminum is found in the engines of automobiles, in the hulls of boats. It is also used in many parts of airplanes. In fact, the huge "airbus" planes would probably never have been produced if aluminum did not exist. By making vehicles lighter in weight aluminum has greatly reduced the amount of fuel needed to move them. Aluminum is also being used extensively in the building industry in some countries.
Since aluminum is such a versatile(多用的) metal, it is fortunate that bauxite(铝土矿) , which is one of its chief sources, is also one of the earth's most plentiful substances. As the source of aluminum is almost inexhaustible, we can expect that more and more uses will be found for this versatile metal.
The price of aluminum was sharply reduced when people discovered a new refining process with the aid of______.
A.wind power
B.solar energy
C.hydraulic power
D.electricity
How much energy given off by the sun reaches the earth?
A.100 % but indirectly
B.5 %
C.0.5
D.only a very tiny amount
To a philosopher, wisdom is not the same as knowledge. Facts may be known in enormous numbers without the knower of them loving wisdom. Indeed, the person who possesses encyclopedic (学识渊博的) information may actually have a genuine contempt (轻视) for those who love and seek wisdom. The philosopher is not content with a mere knowledge of facts. He desires to combine and evaluate facts, and to examine beneath the obvious to the deeper orderliness behind the immediately given facts. Insight into the hidden depths of reality, perspective (洞察) on human life and nature in their entirety, in the words of Plato, to be a spectator of time and existence--these are the philosopher's objectives. Too great an interest in the small details of science, may, and often does, obscure these basic objectives.
Philosophers assume that the love of wisdom is a natural gift of the human being. Potentially every man is a philosopher because in the depths of his being there is an intense longing to penetrate to the meaning of the mysteries of existence. The inner deep longing expresses itself in various ways prior to any actual study of philosophy as a technical branch of human culture. Consequently every human being in so far as he has ever been or is a lover of wisdom has, to that extent, a philosophy of life.
The title below that best expresses the idea of this passage is ______.
A.The Potential Philosopher
B.The Philosophy of Plato
C.The Philosopher Versus the Scientist
D.The Philosopher Defined
The killer bees should not be coming at all. Nature did not put them on this direct path for the United States; human beings did. The killer bees are from Africa. But in 1957 a scientist from Brazil got some of these killer bees for his experiments. The aim was to produce a better bee. However, an accident happened: a guest beekeeper let twenty-six of the queen bees escape by mistake. Before long, groups of killer bees took off for the woods.
Since that time, the wild killer bees have multiplied(繁衍) many times over. By 1998, their population was over 1015. They have spread all over South America, Central America, and most of Mexico. The United States is the next stop.
Are the killer bees really killers? Yes, they are. In their first thirty years in America, they have killed thousands of hens, pigs, and other animals. While no one knows the exact number, it is believed that several hundred people have also been killed.
So be careful. Killer bees are on the way. Scientists have no idea what to do with them yet. There must be a way.
We know from the passage that killer bees will spread to the United States ______.
A.from north
B.from south
C.from west
D.from east
First, sometimes early scientists have an idea which is correct, but scientists in later centuries do not believe it. For example, about 270 B. C., a Greek scientist had an idea which we all believe today: The earth moves around the sun. But for the following 1,600 years scientists did not believe this. In their opinion, the sun clearly moved around the earth. They discovered the truth again only in the fifteenth century!
The second fact of history that many people forget is this: Ancient does not mean primitive. For example, the ancient Egyptians knew a great deal about the stars; they used this knowledge to find their way across the oceans. Two thousand years ago a Greek scientist who lived in Egypt calculated the distance around the earth. The results of his calculations were close to the real distance we know today! So the ancients had a great deal of scientific knowledge. They also had skills which equaled the skills of to- day. For example, 1,300 years ago and before, fishermen in Ireland built their boats of wood and leather. Today some fishermen in Ireland still make boats of the same de- sign. They use tools and materials which are not very different from the tools and materitals which their ancestors used. Why? The ancient design of the boats was good, and with skillful sailors, these boats can sail in all kinds of weather.
Clearly long before the sixteenth century, people had the skill, the knowledge and the equipment which were necessary for long journeys by sea. The world did not have to wait until the sixteenth century for its first explorers!
Which of the following statements is consistent with the passage?
A.According to the writer, we only began to really explore the world in the sixteenth century.
B.In the history of science, people sometimes have to discover a fact a second time.
C.The ancient Egyptians had very little knowledge about the stars.
D.The writer agrees with many Americans and Europeans except for the two facts mentioned in the passage.
The oldest kind of computer is the abacus, used in China since the sixth century. In the seventeenth century an adding machine was invented, but the first large, modern computer was built in 1973. A few years later a computer could do 5,000 additions per second. Now the computations are so fast that they are measured in nanoseconds.
Today most computers are stored-program computers, that is, they have a memory. They are getting smaller and smaller, and computing faster and faster. Even in a large computer, the part that does the actual computing is about the size of the end of a finger.
Computers can do all kinds of work. When someone buys something in a department store, in formation about the sale goes into a computer. A scientist can talk to the computer about the rocks, and the computer answers the questions. A doctor can talk to the computer and explains what is wrong with a patient. If the doctor asks why, the computer goes through its stored information and ex plains exactly why.
When early humans began fanning, it was a revolutionary change in human life. It was hundreds of thousands of years later that people developed a writing system. In less than fifty years people have developed computers that can do most of the things humans can do. This could be a frightening development.
The oldest kind of computer, the abacus, has been used since ______.
A.600
B.700
C.800
D.500
Thomas Jefferson was inaugurated (举行就职典礼) on March 4, 1801. He was the first President to take the oath of office (宣誓就职) in the nation's permanent capital, Washington, D.C. Although Washington was a new city, it was already familiar to President Jefferson. In fact, Jefferson had helped plan the capital's streets and pubic buildings. (79) Besides being a city planner and architect, the new President was a writer, a scientist, and the inventor of several gadgets (小装置) and tools.
After his inauguration, Jefferson moved into the Presidential Palace. The Palace was more than a home; it contained offices for the President and some of his staff and advisors. It also included dining and reception rooms, where the President could entertain congressmen. However, President Jefferson did not give many formal parties. This was partly because there was no First Lady; Jefferson's wife died in 1782. But it was also because Jefferson liked to live in a simple fashion. Once, he showed up for an important meeting wearing old clothes and down-at-the-heel slippers! Neither Washington nor Adams would ever have dressed so casually.
Jefferson was different from the first two Presidents in other ways, too. (80) He disagreed with them about how the country should be run, and about what part a President should play in running it.
Which of the following statements about Washington, D.C. can be correctly inferred from the passage?
A.The Presidential Palace was not located there.
B.It contained many old buildings in 1801.
C.It was not the first capital of the United States.
D.Thomas Jefferson was a newcomer there in 1801.
It is understood that in a favorable climate______.
A.tree rings grow close together
B.tree rings grow far apart
C.trees in New Mexico will grow big and tall
D.people can cut down most of the trees in New Mexico
A.a scientist come to
B.was a scientist come to
C.a scientist did come to
D.did a scientist come to