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问题 选择题

下列说法不正确的是（    ）

A．原电池中，负极上发生的反应是氧化反应

B．原电池中，电流从负极流向正极

C．铜锌原电池工作时，溶液中的阴离子向负极移动，阳离子向正极移动

D．碱性锰锌电池是一次电池，铅蓄电池是二次电池

答案

答案：B

在原电池中较活泼的金属作负极，失去电子，发生氧化反应。电子经导线传递到正极上，所以溶液中的阳离子向正极移动，阴离子向负极移动。正极得到电子，发生还原反应。所以选项B是错误的，其余都是正确的，答案选B。

阅读理解

阅读理解。

      Peter wanted very much to be a soldier when he was a child. So he joined the army (军队) when

he was eighteen, and for several months he was taught how to be a good soldier. He did quite well in

everything except shooting. One day he and his friends were practicing their shooting (射击), and all

of them were doing quite well except Peter. After he had shot at the target (靶) nine times and hadn't

hit it once, the officer who was trying to teach the young soldiers to shoot said, "You are quite hopeless,

Peter. I don't waste your last bullet! Go behind that wall and shoot yourself with it!"

       Peter felt ashamed (难为情). He went behind the wall and a few seconds later, the officer and the

other soldiers heard the sound of a shot.

       "Oh, dear!" the officer said. "Has that silly man really shot himself?" He ran behind the wall as quickly

as he could, but Peter was all right."I'm sorry, sir," he said, "but I missed again."

1. Peter joined the army in order to ______?

A. be a soldier

B. be good at shooting

C. make friends

D. get a good job

2. The officer thought Peter was hopeless because ______.

A. he didn't know how to use a gun.

B. he didn't get along well with other soldier.

C. he was poor at shooting.

D. he couldn't do anything well.

3. What the officer said at the end of the first paragraph(段落) shows that ______.

A. the officer really wanted Peter to die

B. the officer was very angry with Peter

C. the officer was not a kind-hearted man

D. the officer was afraid that Peter would shoot himself

4. The officer felt ______ when he heard the sound of a shot.

A. ashamed

B. frightened

C. excited

D. disappointed (失望)

5. What happened at the end of the story?

A. Peter became a good soldier.

B. Peter killed himself behind the wall.

C. The officer was pleased with Peter in the end.

D. Peter missed the target for the tenth time.

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完形填空
In the old days, the Olympic Games were religious（宗教的）activities. Greece held the first Olympic Games in the eighth century B.C. The Games lasted just for one day and there were only races. Only men could be in the races. Women had no right（权利）to take part in the Olympic Games until 1912.
The Olympic Games were stopped in the fourth century. Then they started again in Athens in 1896. This was the beginning（开始）of the modern Olympics. Since then, the Olympics Games have been held every four years. The Olympic rings are a symbol of the Olympic Games. There are five rings, and they stand for the five parts of the world. The colors of the rings are blue, yellow, black, green and red. You can find at least one of these colors in the flag of each country in the world.
The IOC（国际奥委会）makes rules for the games, so all the athletes have the same chance to win. Winning in the Olympics is a great honor. An athlete who wins at the Olympics is the best in the world. “Faster, higher, stronger”is the motto of the Olympics.
任务型阅读：根据短文内容填写下列空格。
The motto of the Olympic Games: “ Faster, higher,   小题1: ”
A symbol of the Olympic Games: the Olympic   小题2: 
The five rings means the five parts of the   小题3: 
One of the colors of the rings:  小题4: 
The beginning of the modern Olympics:   小题5: 
 小题6: could not take part in the Olympic Games until 1912.
 
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