单选题 If you want to stay young, sit down and have a good think. This is the research finding of a team of Japanese doctors, who say that most of our brains are not getting enough exercise—and as a result, we are ageing unnecessarily soon.
Professor Taiju Matsuzawa wanted to find out why otherwise healthy farmers in northern Japan appeared to be losing their ability to think and reason at a relatively early age, and how the process of ageing could be slowed down.
With a team of colleagues at Tokyo National University, he set about measuring brain volumes of a thousand people of different ages and varying occupations.
Computer technology enabled the researchers to obtain precise measurements of the volume of the front and side sections of the brain, which relate to intellect (智能) and emotion, and determine the human character. (The rear section of the brain, which controls functions like eating and breathing, does not contract with age, and one can continue living without intellectual or emotional faculties.
Contraction of front and side parts—as cells die of—was observed in some subjects in their thirties, but it was still not evident in some sixty-and seventy- year-olds.
Matsuzawa concluded from his tests that there is a simple remedy to the contraction normally associated with age—using the head.
The findings show in general terms that contraction of the brain begins sooner in people in the country than in the towns. Those least at risk, says Matsuzawa, are lawyers, followed by university professors and doctors. White collar workers doing routine work in government offices are, however, as likely to have shrinking brains as the farm worker, bus driver and shop assistant.
Matsuzawa"s findings show that thinking can prevent the brain from shrinking. Blood must circulate properly in the head to supply the fresh oxygen the brain ceils need. "The best way to maintain good blood circulation is through using the brain," he says, "Think hard and engage in conversation. Don"t rely on pocket calculators. "

单选题 According to the Japanese doctors, the reason for ageing is that ______.

【正确答案】 B

【答案解析】[解析] 细节题。题干意为“日本医生认为人类衰老的原因是”。根据题干中Japanese doctors和the reason for ageing定位至第一段第二句后半部分，日本医生说我们大多数人的大脑没有得到足够的锻炼，这就导致衰老得比较快。B选项(我们的大脑缺乏足够的锻炼)符合题意，故B为正确答案。

单选题 In order to finish this research, the doctors need to measure ______.

单选题 The doctor"s test shows that ______.

单选题 The word "subjects" in Paragraph 5 means ______.

【正确答案】 C

【答案解析】[解析] 释义题。题干意为“第五段中‘subjects’一词意思为”。该题可运用代入法将选项一一代入原文确定答案。A项意为“考虑在内的某件事”，B项意为“所学习的学科分支”，C项意为“试验中被研究的人们”，D项意为“一个国家中除最高统治者之外的任何一员”。显然，只有C选项符合原文意思，故C为正确答案。