46. The author begins his article with Edmund Burke's words to_____.
主旨题，文章各段主题句
47. Misled people tend to think that using an animal in research is_____.
细节题，定位词所在句
48. The example of the grandmotherly woman is used to show the public's_____.
结构题，例子对应的论点句
49. The author believes that, in face of the challenge from animal rights advocates, scientists should_____.
细节题，定位词所在句
50. From the text we learn that Stephen Cooper is_____.
细节题，定位词所在句
步骤四，动作决定论
