We can achieve knowledge either actively or passively（被动地）. We achieve it active

We can achieve knowledge either actively or passively（被动地）. We achieve it actively by direct experience, by testing and proving an idea, or by reasoning.

We achieve knowledge passively by being told by someone else. Most of the learning that takes place in the classroom and the kind that happens when we watch TV or read newspapers or magazines is passive. Conditioned as we are to passive learning, it’s not surprising that we depend on it in our everyday communication with friends and co-workers.

Unfortunately, passive learning has a serious problem. It makes us tend to accept what we are told even when it is little more than hearsay and rumor(谣言).

Did you ever play the game Rumor? It begins when one person writes down a message but doesn’t show it to anyone. Then the person whispers it, word for word, to another person. That person, in turn, whispers it to still another, and so on, through all the people playing the game. The last person writes down the message word for word as he or she hears it. Then the two written statements are compared. Typically, the original message has changed.

That’s what happens in daily life. The simple fact that people repeat a story in their own words changes the story. Then, too, most people listen imperfectly. And many enjoy adding their own creative touch to a story, trying to improve on it, stamping（打上标记）it with their own personal style. Yet those who hear it think they know.

This process is also found among scholars and authors: A statement of opinion by one writer may be re-stated as fact by another, who may in turn be quoted by yet another; and this process may continue, unless it occurs to someone to question the facts on which the original writer based his opinion or to challenge the interpretation he placed upon those facts.

48. According to the passage, passive learning may occur in _______.

   A. doing a medical experiment

   B. solving a math problem

   C. visiting an exhibition

   D. doing scientific reasoning

49. The underlined word “it” in Paragraph 2 refers to _____.

   A. active learning

   B. knowledge

   C. communication

   D. passive learning

50. The author mentions the game Rumor to show that _____.

   A. a message may be changed when being passed on

   B. a message should be delivered in different ways

   C. people may have problems with their sense of hearing

   D. people tend not to believe in what they know as rumor

51. What can we infer from the passage?

   A. Active learning is less important.

   B. Passive learning may not be reliable.

   C. Active learning occurs more frequently.

   D. Passive learning is not found among scholars.

 解析：

本文是一篇说明文，主要介绍了被动获得知识所存在的一个严重的问题――被告知的可能是谣言。并用现实生活中简单的事例加以说明。

      48．C  推理判断题。由文章第二段前两句we achieve knowledge passively by being told by some else,……in the classroom and the kind that happens when we watch TV of read newspaper or magazines is passive可知被动学习是指由别人告知所获得的知识。故选C.  A、B、D   都是主动学习。

      49. D  推理判断题。根据it 所在句可知这个代词指代的是前句所提的被动学习，句意：在日常生活中依靠被动学习并不奇怪。

      50．A 

      推理判断题。通过第四段最后一句可知，原始的含义改变了，例证了第三段提出的论点“被动学习使我们接受被告知的事物，甚至有时是谣言。”因此A项为正确项。