题目内容

Tom sat under a tree chatting with his friends and _____ his teacher, stood up in no time.

  A. seeing      B. seen              C. saw       D. to see

A


解析:

略

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语音知识(共5小题；每小题1分，满分5分)

从A、B、C、D四个选项中，找出其划线部分与所给单词的划线部分读音相同的选项。

例：have    A．gave      B．save      C． hat      D． made

  答案是C。

1．meant      A．steak          B．breathe      C．peasant        D．really

2．wounded    A．cousin        B．encourage    C．housewife      D．route

3．weekday    A．Wednesday    B．nowadays    C．Monday        D．says

4．disappeared  A．practised      B．knocked      C．obeyed        D．escaped

5．design     A．bargain        B．foreign       C．strange        D．geography

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 high 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, presently the size and thickness of a penny, intended to power various micro/nanoelectromechanreal systems (M/NEMS). 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(晶体结构) 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 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 introduce 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

书面表达（满分25分）

2011年3月22日——第十九届世界水日。假设你是银川一中某班的学生 ，22日参加了你班开展的一系列节水宣传活动。请根据以下四幅图的先后顺序，以日记的形式记录当天的活动内容

。

注意：词数100字左右。

提示词：宣传材料leaflets；危机crisis; 干旱draught ;  

March 22,2011  Tuesday                                               Sunny

 

Today is 19th World Water Day._______________________________________________

________________________________________________________________________________

Why are you so anxious? It isn’t your problem              .

A. on purpose       B. in all              C. on time             D. after all

Einstein liked Bose’s paper so much that he ____ his own work and translated it into German.

A. gave off          B. turned down          C. took over               D, set aside

_______ in his school that many of his fans want to get close to him.

A. So is he popular               B. So popular is he

C. So popular he is                     D. So he is popular

His parents died when he was very young, so he was         by his grandmother.

    A. brought up           B. grown up         C. taken up             D. picked up

I can’t find the recorder in the room. It ________ by someone.

A. may take                 B. may have been taken away

C. must have taken away      D. needn’t have been taken away

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