At that time ,his country was ____ Japan, so hearing from him was extremely difficult.

A. at war with      B. at the war with   C. at war against  D. during the war with

Batteries can power anything from small sensors to large systems. While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves. University of Missouri (MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.

“To provide enough power, we need certain methods with energy density (密度),” said Jae kwon, assistant professor of electrical and computer engineering at MU. “The radioisotope (放射性同位素) battery can provide power density that is much higher than chemical batteries.”

Kwon and his research team have been working on building a small nuclear battery, recently the size and thickness of a penny, intended to power various micro/nano-electromechanical systems (M/NEWS). Although nuclear batteries can cause concerns, Kwon said they are safe.

“People hear the word ‘nuclear’ and think of something very dangerous,” he said. “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”

His new idea is not only in the battery’s size, but also in its semiconductor (半导体). Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor.

“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure (晶格结构) of the solid semiconductor, ” Kwon said. “By using a liquid semiconductor, we believe we can minimize that problem.”

Together with J. David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery. In the future, they hope to increase the battery’s power, shrink its size and try with various other materials. Kwon said that the battery could be thinner than the thickness of human hair.

Which of the following is true of Jae Kwon?

A. He teaches chemistry at MU.                 

B. He developed a chemical battery.

C. He is working on a nuclear energy source.     

D. He made a breakthrough in computer engineering.

Jae Kwon gave examples in Paragraph 4 ________.

A. to show chemical batteries are widely applied

B. to indicate nuclear batteries can be safely used

C. to describe a nuclear-powered system            

D. to introduce various energy sources.

Liquid semiconductor is used to ________ .

A. get rid of the radioactive waste             

B. test the power of nuclear batteries

C. decrease the size of nuclear batteries      

D. reduce the damage to lattice structure

According to Jae Kwon, his nuclear battery ________.

A. uses a solid semiconductor                        B. will soon replace the present ones

C. could be extremely thin                                D. has passed the final test

The text is most probably a ________.

A. science news report                                     B. book review

C. newspaper ad                                              D. science fiction story

Years ago, a cigarette commercial asked if you were smoking more, but enjoying it less. That describes the way many of us live today. We are doing more, but enjoying it less. And when that doesn’t work, we compound the problem. In our frantic search for satisfaction, we try stuffing still more into our days, never realizing that we are taking the wrong approach.

The truth is simple; so simple it is hard to believe. Satisfaction lies with less, not with more. Yet, we pursue the myth that this thing, or that activity, will somehow provide the satisfaction we so desperately seek.

Arthur Lindman, in his devastating book, “The Harried Leisure Class,” described the futility of pursuing more. His research focused on what people did with their leisure time. He found that as income rose, people bought more things to occupy their leisure time. But, ironically, the more things they bought, the less they valued any one of them. Carried to an extreme, he predicted massive boredom in the midst of tremendous variety. That was more than twenty years ago, and his prediction seems more accurate every year.

Lindman, of course, is not the first to discover this. The writer of Ecclesiastes expressed the same thought thousands of years ago. It is better, he wrote, to have less, but enjoy it more.

If you would like to enjoy life more, I challenge you to experiment with me. How could you simplify your life? What could you drop? What could you do without? What could you stop pursuing? What few things could you concentrate on?

The more I learn, the more I realize that fullness of life does not depend on things. The more I give up, the more I seem to gain. But words will never convince you. You must try it for yourself.

Arthur Lindman predicted twenty years ago that ______.

A. more things brought more value   B. the more people had, the less they valued them

C. people didn’t like to pursue more   D. massive boredom came from less variety

What does the article suggest to make our life happier?

A. To enjoy more things.             B. To buy more things.

C. To sell things we do not need.       D. To get rid of useless things.

The passage is probably written to ___________.

A. introduce Arthur Lindman and his book       B. tell the readers what is satisfaction

C. introduce how to simplify people’s life         D. persuade people to simplify their life

Jack is good, kind, hard-working and intelligent. _____, I can't speak too highly of him.

A. As a result   B. By the way     C. On the whole   D. In a word

____ computers are of great benefit to the development of science and technology.

    A. The fact is what                  B. That the fact is   

    C. What the fact is that             D. The fact is that