问题 单项选择题

下列关于骨肉瘤的描述错误的是()

A.多见于10~25岁的青少年

B.不易向肺转移

C.好发于胫骨上端或股骨下端

D.X线片可有Codman三角

E.血清碱性磷酸酶增加

答案

参考答案:B

多项选择题
阅读理解

阅读理解。

     It was a village in India. The people were poor. However, they were not unhappy. After all, their

forefathers had lived in the same way for centuries.

     Then one day, some visitors from the city arrived. They told the villagers there were some people

elsewhere who liked to eat frog's legs. However, they did not have enough frogs of their own, and so

they wanted to buy frogs from other places.

     This seemed like money for nothing. There were millions of frogs in the fields around, and they were

no use to the villagers. All they had to do was catch them. Agreement was reached, and the children were

sent into the fields to catch frogs. Every week a truck arrived to collect the catch and hand over the money.

For the first time, the people were able to dream of a better future. But the dream didn't last long.

     The change was hardly noticed at first, but it seemed as if the crops were not doing so well. More

worrying was that the children fell ill more often, and, there seemed to be more insects around lately.

     The villagers decided that they couldn't just wait to see the crops failing and the children getting weak.

They would have to use the money earned to buy pesticides (杀虫剂) and medicines. Soon there was no

money left.

     Then the people realized what was happening. It was the frog. They hadn't been useless. They had been

doing an important job-eating insects. Now with so many frogs killed, the insects were increasing more

rapidly. They were damaging the crops and spreading diseases.

     Now, the people are still poor. But in the evenings they sit in the village square and listen to sounds of

insects and frogs. These sounds of the night now have a much deeper meaning.

1. From Paragraph 1 we learn that the villagers _____.

A. worked very hard for centuries

B. dreamed of having a better life

C. were poor but somewhat content

D. lived a different life from their forefathers

2. Why did the villagers agree to sell frogs?

A. The frogs were easy money.

B. They needed money to buy medicine.

C. They wanted to please the visitors.

D. The frogs made too much noise.

3. What might be the cause of the children's sickness?

A. The crops didn't do well.

B. There were too many insects.

C. The visitors brought in diseases.

D. The pesticides were overused.

4. What can we infer from the last sentence of the text?

A. Happiness comes from peaceful life in the country.

B. Health is more important than money.

C. The harmony between man and nature is important.

D. Good old days will never be forgotten.