单选题Which of the following is true about the U.S. Navy underwater listening network?.

单选题In a telephone survey of more than 2,000 adults, 21% said they believed the sun revolved around the earth. An 1 7% did not know which revolved around 2 . I have no doubt that 3 all of these people were 4 in school that the earth revolves around the sun; 5 may even have written it 6 a test. But they never 7 their incorrect mental models of planetary 8 because their everyday observations didn"t support 9 their teachers told them: People see the sun moving 10 the sky as morning tunas to night, and the earth seems stationary 11 that is happening. Students can learn the right answers 12 heart in class, and yet never combined them 13 their working models of the world. The objectively correct answer the professor accepts and the 14 personal understanding of the world can 15 side by side, each unaffected by the other. Outside of class, the student continues to use the 16 model because it has always worked well 17 that circumstance. Unless professors address 18 errors in students" personal models of the world, students are not 19 to replace them with the 20 one.

单选题There has been a great increase in retail sales, ______ . A. does there B. isn't there C. hasn't there D. isn't it

单选题In return for their hospitality, Mr. and Mrs. Brown decided to hold a party to________ their neighbours.

单选题With prices ______ so much, it's hard for the company to plan a budget.

单选题A new technique ______, the yields as a whole increased by 20 percent.

单选题When he tried to make a ______ , he found that the hotel was completely filled because of a convention. A. reservation B. claim C. mess D. revision

单选题{{B}}TEXT E{{/B}} Researchers have established that when people are mentally engaged, biochemical changes occur in the brain that allow it to act more effectively in cognitive areas such as attention and memory. This is true regardless of age. People will be alert and receptive if they are faced with information that gets them to think about things they are interested in. And someone with a history of doing more rather than less will go into old age more cognitively sound than someone who has not had an active mind. Many expert are so convinced of the benefits of challenging the brain that they are putting the theory to work in their own lives." The idea is no necessarily to learn to memorize enormous amounts of information," says James Fozard, associate director of the National Institute on Aging." Most of us don' t need that kind of skill. Such specific training is of less interest than being able to maintain mental alertness." Fozard and others say they challenge their brains with different mental skills, both because they enjoy them and because they are sure that their range of activities will help the way their brains work. Gene Cohen, acting director of the same institute, suggests that people in their old age should engage in mental and physical activities individually as well as in groups. Cohen says that we are frequently advised to keep physically active as we age, but older people need to keep mentally active as well. Those who do are more likely to maintain their intellectual abilities and to be generally happier and better adjusted." The point is, you need to do both," Cohen says," Intellectual activity actually influences brain-cell health and size."

单选题The word "paradox" ( Para. 1, Line 1 ) means" ______ ".

单选题The police asked the young man to give a truthful answer ______ to the facts.

单选题 Question 29 to 30 are based on the follwing news. At the end of the news item, you will be given 10 seconds to answer the questions. Now, listen to the news.

单选题Scientific research results can now be quickly ______ to factory production. A. used B. applied C. tried D. practiced

单选题They stood still on the top of a mound, gazing out over the endless______of the grassland. A. space B. expanse C. stretch D. land

单选题What do we know about Mike?

单选题A nation's merchant marine is made up of its commercial ships and people ______ them. A. they operate B. who operate C. they operate of D. do they operate