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问题 单项选择题

在人类的身体中，细菌的数量要远远多于人体的细胞，其中大部分细菌对人是有益的，有助于我们消化食物。但是，肠道内的有益细菌有时会死亡或被清除。阑尾不仅能重启在患病时被删除掉的肠道系统内的有益细菌，而且因其所处的位置正好在正常的食物流以下，作为大肠的死胡同，它贮存了各种各样的细菌。这些都说明阑尾就像一个安全的备份盘。从形状上看，阑尾就像一个蠕虫似的器官。实际上，它是一个细菌加工厂，培养着对人有益的细菌。但是，在疾病流行之时，如霍乱影响到某个地区，阑尾就不可能轻而易举地培养出细菌。 下列关于“备份盘”和“加工厂”的解说，不正确的一项是：

A．阑尾就像一个“备份盘”，是因为它能重启因疾病被删除掉的肠道系统内的有益细菌

B．在疾病流行之时，阑尾不能培养出细菌，所以它并非严格意义上的细菌加工厂

C．形状像蠕虫似的阑尾，能培养对人有益的细菌，就像一个细菌加工厂

D．阑尾贮存了各种各样的细菌，且处在正常的食物流以下，作为“备份盘”，很安全

答案

参考答案：B

解析： B项不正确，原文只说“阑尾就不可能轻而易举地培养出细菌”，而不是“阑尾不能培养出细菌”。

阅读理解
阅读理解.
     Douglas Corrigan had a dream. He wanted to fly a plane across the Atlantic Ocean by himself. He
bought a used airplane. Then he asked for permission (允许) to fly it across the ocean. People from the
government looked at his shabby, old plane. They said no because the plane didn't look safe enough to
make the trip smooth.
      Sometime later Corrigan asked for permission to fly from New York to California without stopping.
This time the answer was yes. Comgan climbed into his plane early one morning in July of 1938. His gas
tank (油箱) was full. He had a box of cookies. He waved good-bye and took off.
     Comgan didn't go west to California, though. Instead, he headed northeast. Twenty-six hours later, he
landed in Dublin, Ireland. He had flown the Atlantic Ocean after all.
    What happened? According to Corrigan, the needle (针) on his compass (罗盘) was pointed the wrong way.
     Comgan's dream had come true. Was it an accident, or did he plan it? No one but "Wrong Way"
Corrigan knows for sure.
1. At first people from the government said no to Corrigan because they _____.
A. knew he was not a good pilot
B. thought the weather was too bad
C. didn't like his plan
D. didn't think his plane was safe
2. In Paragraph 1, the word "shabby" means _____.
A. very fast
B. brightly painted
C. in poor condition (条件)
D. well built
3. Where did Corrigan land after his flight?
A. England.
B. California.
C. New York.
D. Ireland.
4. The reader can tell from this passage that Corrigan _____.
A. fell asleep during his flight
B. was afraid of new challenges
C. believed in himself and his dream
D. made the same flight many times
5. Read the first sentence of the summary (摘要) below.      
Summary
Douglas Corrigan dreamed about flying across the Atlantic Ocean by himself.
Which of these best completes the summary?    
A. He bought an old plane to use for the flight. He asked permission to make the flight, but he did not get it.
B. He got permission only to fly across the United States. He flew across the Atlantic instead and said it
    was by mistake,
C. He got permission to fly from New York to California without stopping. No one had done that before
    in an old plane.
D. He bought an old airplane and mended it. It didn't look very good, but it still could fly well and go far.
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选择题

两根相同长度的细线轻绳悬挂着一个物体，现在增大悬挂点A、B间的距离距而系统仍静止，以下说法正确的是（　　）

A．细线绳子中的拉力不变

B．细线对物体的拉力增大

C．细线对物体的拉力减小

D．物体受到的合力增大
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