Passage 3

Once upon a time, two brothers, Jack and Tom, who lived on neighboring farms, fell into conflict. For the past 20 years, they had been on good terms farming side by side, sharing machinery, and trading labor and goods as needed. The dispute began with a small misunderstanding and grew into a major difference, and finally exploded into an exchange of bitter words followed by weeks of silence.

One morning there was a knock on a door. It was a carpenter looking for a few day’s work. Jack offered him a job saying, “Look across the steam at that farm. That’s my neighbor, in fact, it’s my younger brother. There used to be a meadow between us. Last week he pulled down the dam on the small river and now there is a stream instead. Well, he may have done this to offend me, but I’ll do him one better

"See that pile of lumber (木材) by the house? I want you to build me a fence, a 8-foot fence." The carpenter said, “I think I understood the situation. Show me the nails and the post- hole digger 打桩机）and I’ll be able to do a job that please you.”

Jack had to go into town, so he helped the carpenter get the material ready and then he was off for the day. The carpenter worked hard all that day measuring, sawing and nailing. About sunset when Jack returned, the carpenter had just finished his job.

Jack's eyes opened wide, his jaw dropped. There was no fence there at all. It was a bridge--the bridge stretching from one side of the stream to the other! A fine piece of work! His younger brother was coming toward them with hands outstretched, “you are quite a fellow to build this bridge after all I’ve said and done,”  The two brothers stood at each end of the bridge, and then they met in the middle, taking each other’s hand.

They turned to see the carpenter lift his toolbox onto his shoulder. "No, wait! Stay a few days, I have a lot of other projects for you,” said Jack, “I’d love to stay on.” The carpenter said, “but I have many more bridges to build."

41. In the past 20 years, Jack and Tom kept their  relationship ________.

A. serious B. tense C. distant D. close

42.Jack decided to build a fence to _______.

A.protect himself B. fight back C. please Tom D. give in

43.What does underlined expression “quite a fellow" mean in paragraph 5?

A. A powerful man

B. A rich man 

C. A generous man

D. A capable man

44.The carpenter built the bridge instead of a fence to help Jack and Tom

A. meet each other

B. store the lumber

C. regain brotherly affection

D. renew their business

45.What can we learn from the passage?

A.Better make friends than make enemies.

B.A good friend brings a far land near.

C.Family ties are close than social relations.

D.A tooth for a tooth.

Passage 4

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. The researchers at university of Missouri (MU) are developing a nuclear energy source that is smaller, lighter and more efficient.

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

Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various systems. 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 pacemakers, space satellites and under water systems.”

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

“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 (晶体结构）of the solid semiconductor,” Kwon said, “by using a liquid semiconductor, we believe we can minimize the 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 their battery could be thinner than the thickness of human hair.

46.The passage gets started by ________.

A. an introduction

B. an example

C. a question

D. a conclusion

47.What do you know about Jae Kwon?

A.He is teaching chemistry at MU.

B.He developed a chemical battery.

C.He was good at computer engineering.

D.He is working on a nuclear energy source.

48.Which of the following is true according to paragraph 3 and 4?

A.The writer introduces methods of providing power density.

B.The writer intends to describe a nuclear-power system.

C.The writer introduces nuclear batteries which/that can be safely used.

D.The writer is likely to show chemical batteries are widely applied.

49.Liquid semiconductor is used to _____.

A.control the lattice structure

B.show the power of nuclear batteries

C.decrease the size of nuclear batteries

D.reduce the damage to lattice structure

50.The passage is most probably from a _____.

A. science news report

B. book review

C. science fiction novel 

D. newspaper advertisement