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问题 选择题

“太阳大，地球小，太阳带着地球跑；地球大，月球小，地球带着月亮跑。”重温童谣，结合所学知识，回答童谣中涉及的天体系统层次共有

A．一个

B．两个

C．三个

D．四个

答案

答案：B

本题涉及的天体系统有太阳系和地月系二级。选择B项。

单项选择题

For years and years people have been saying that the railways are dead. "We can do without railways" people say, as if motorcars and planes made the railways unnecessary. We all keep hearing that trains are slow, that they lose money, that they’re dying. But this is far from the truth. In these days of expensive oil, the railways have become highly competitive with motorcars and planes. If you want to carry people or goods from place to place, they’re cheaper than planes.
And they have much in common with planes. A plane goes in a strange line and so does a railway. What is more, it takes you from the heart of a city into the heart of another. It doesn’t leave you as a plane does, miles and miles from the city center. It doesn’t hold you up as a car does, in endless traffic jams. And a single train can carry goods which no plane or motorcar could ever do.
Far from being dead, the railways are very much alive. Modern railway lines give you a smooth, untroubled journey. Where else can you eat well, sleep in comfort, feel safe and enjoy the scene while you are traveling at speed at the same time And we are only at the beginning. For we have just entered the age of super-fast trains, traveling at 150 miles an hour and more. Soon we will be wondering why we spent so much on motorways we can’t use because we have not enough money to buy the oil and planes we can’t fly in for the same reason.

Which of the following statements best sums up the passage

A．The railways are dead now.

B．Motorcars and planes have made the railways unnecessary.

C．We’ve entered the age of super-fast trains.

D．The advantages of the railways enable them to be alive even nowadays.
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多项选择题

基础研究能力是一个国家科技创新实力的重要体现，改革开放以来，我国基础研究取得了瞩目成就，但与世界发达国家相比仍存在很多薄弱之处（）。

A.很多基础研究采用项目导向缺乏系统性和整体性

B.基础研究研发投入强度偏低

C.缺乏重大原创性、高质量的科研成果

D.国家对基础研究不重视，认为其不重要
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