题目内容
It is over 40 years since first atomic bomb was dropped on a major city in Japan. Yet even now its effects are showing themselves and may continue to do so for years to come. Much effort and human energy have been used to try to prevent such a terrifying thing from happening again. So far there is no guarantee that it will not. Countries which already possess nuclear knowledge and resources have bombs stored away which are powerful enough to wipe out all life on earth. But this is not all. Other countries, which previously were not so advanced in technology, are gradually buying materials that can be used for making atomic devices. This nuclear energy will naturally be of great value in helping the economy of poorer nations.
The generation of electricity through nuclear power came directly from the original work on the atom bomb. Because of the increase in demand for energy and the possibility of decreasing supplies of oil and natural gas, the interest in electricity has increased. One of the by-products of nuclear power stations is plutonium (钸) produced from unclear fuel: plutonium is ingredient (成分) in bomb-making. It means that there are far more opportunities for the manufacture of bombs.
This brings the problem to a full circle again. How can something so valuable and useful be controlled so that it works for the benefit and not the destruction of man?
9. The effects of dropping the first atomic bomb ________.
A. are not over B. may go on forever
C. could last much longer D. will not be over in the near future
10. The writer says that enough atomic bombs have already been manufactured to ________.
A. wipe out Japan B. last forever
C. act as a peace-keeping device D. destroy all living things
11. The advantage of less developed countries being able to make atomic devices is that it ______.
A. gives them more opportunities for work B. will help poor countries to become richer
C. will enable them to make better explosives D. will be of great value to them
12. The second paragraph tells us that the increased demand for electricity today ________.
A. has led to the decrease in supplies of oil
B. means that more countries are interested in nuclear power
C. has increased the risk of accidental explosions
D. has increased the very means of producing more atomic bombs
9-12 ADBD
解析:
9. A 细节理解题。根据第一段第二句Yet even now its effects are showing themselves and may continue to do so for years to come可知。
10. D 细节理解题。根据第一段“…have bombs stored away which are powerful enough to wipe out all life on earth”一句可知。
11. B 细节理解题。根据第一段“This nuclear energy will naturally be of great value in helping the economy of poorer nations”一句可知。
12. D 段落主旨题。根据第二段最后一句“It means that there are far more opportunities for the manufacture of bombs.”可知。
Almost every machine with moving parts has wheels, yet no one knows exactly when the first wheel was invented or what it was used for. We do know, however, that they existed over 5,500 years ago in ancient Asia.
The oldest known transport wheel was discovered in 2002 in Slovenia. It is over 5,100 years old. Evidence suggests that wheels for transport didn’t become popular for a while, though. This could be because animals did a perfectly good job of carrying farming tools and humans around.
But it could also be because of a difficult situation. While wheels need to roll on smooth surfaces, roads with smooth surfaces weren’t going to be constructed until there was plenty of demand for them. Eventually, road surfaces did become smoother, but this difficult situation appeared again a few centuries later. There had been no important changes in wheel and vehicle design before the arrival of modem road design.
In the mid-1700s, a Frenchman came up with a new design of road—a base layer (层) of large stones covered with a thin layer of smaller stones. A Scotsman improved on this design in the 1820s and a strong, lasting road surface became a reality. At around the same lime, metal hubs (the central part of a wheel) came into being, followed by the pneumatic tyre(充气轮胎) in 1846. Alloy wheels were invented in 1967, sixty years after the appearance of tarmacked roads (柏油路). As wheel design took off, vehicles got faster and faster.
【小题1】What might explain why transport wheels didn’t become popular for some time?
A.Few knew how to use transport wheels. |
B.Humans carried farming tools just as well. |
C.Animals were a good means of transport. |
D.The existence of transport wheels was not known. |
A.It was easier than wheel design. |
B.It improved after big changes in vehicle design. |
C.It was promoted by fast-moving vehicles. |
D.It provided conditions for wheel design to develop. |
A.By giving examples. |
B.By making comparisons. |
C.By following time order. |
D.By making classifications. |
A.The beginning of road design. |
B.The development of transport wheels. |
C.The history of public transport. |
D.The invention of fast-moving vehicles. |