单选题 Medical studies show that only two to five percent of the obese manage to shed unwanted pounds permanently. The rest, after intermittent successes, regain or surpass their starting weights within a couple of years. Why do most reducing programs fail in the long run, and so many dieters put back lost weight? Some experts claim that the gloomy estimates of dieting failure may be exaggerated, since some people do manage to keep off at least some weight, even though they may not achieve the svelte look they desire. Only those who fail dismally in their own dieting efforts enter format reduction programs. So, on an optimistic note, some health professionals point out that most studies never consider those who successfully keep weight off, don't seek medical advice and hence aren't counted in the statistics. Another explanation for failure is that diets set up unreal expectations of a magical cure, often based on absurdly monotonous meal plans that cannot possibly be followed for long. And the very idea of dieting implies a temporary effort you go on the new eating regime only to come off it. Once the diet is over and former eating habits taken up again, people often give themselves permission to binge on foods forbidden while dieting. A further obstacle to successful dieting is the exclusion of certain foods that acquire a special status. No food should be forbidden; it is better to work a little ice cream or dessert into your regime to avoid an irresistible urge to gorge on prohibited items. The all too familiar cycle of yo-yo dieting-endless diets followed by weight regain—may leave dieters worse off than before. Some studies suggest that with each successive fast and feast, metabolic changes make the post-dieting weight regained higher in fat than muscle. Repeated dieting often produces depression, a sense of failure, an intense preoccupation with food, loss of self-esteem and stress from the continual deprivation.

单选题 Why does the writer end up with question in Paragraph 1?

【正确答案】 B

【答案解析】解析：推断题。题目问的是文章第一段以问句结束的原因。定位到文章第一段。开篇指出只有2％到5％的减肥者能够长久地减掉多余体重，其余均以失败告终，第一段最后提出问题：为什么如此多的节食者会反弹呢?由此可知第一段最后是想通过这个问句引出全文的主旨——减肥失败的原因，故选B。

单选题 Can you tell the meaning of the word "svelte" from its context?

【正确答案】 D

【答案解析】解析：释义题。题目问的是svelte一词的意思。根据svelte定位到第二段第一句。svelte本身意思是“苗条的，体态娇美的”，放在此句中意思不符。此处应该是说没有达到减肥者理想的面貌，look“面貌，模样”，所以svelte在这里应该是“理想的，想象的”的意思，故选D。

单选题 According to paragraph 3, dieting failure is caused by______.

单选题 The scientific knowledge of dieting______.

【正确答案】 B

【答案解析】解析：细节题。题目问的是关于节食的科学知识会______。文章最后一段第二句提到“Some studies suggest that with each successive fast and feast，metabolic changes make the post-dieting weight regained higher in fat than muscle” 由此可知，节食的科学知识会让我们熟悉这种无尽的反复的节食一暴食循环恢复会让减肥者复胖，并且比以前更糟糕。故选B。