4.What did Ethan Sims make his subjects（研究对象） do? A)Battle（同...作斗争）their genetic（遗传的） inheritance（遗传）． B)Increase （增加）their weight（体重）． C)Stay（逗留，保持） at home（在家）． D)Lower（降低） their weight． 4.B． 细节题。 利用问题句中的特征词（Ethan Sims）及被选项中的细节信息结构（A：genetic（遗传的） inheritance； B：Increase （增加）their weight； C：Stay（逗留，保持） at home； D：Lower（降低） their weight）共同作为答案线索， 在文章中查找答案相关句： You hear this：“No Wonder you are fat．An you ever do is eat．”You feel sad：“I skip my breakfast and supper．I run every morning and evening．What else can I do?”Basically you can do nothing．Your genes，not your life habits，determine your weight and your body constantly tries to maintain it． Albert Stunkard of the University of Pennsylvania found from experiments that，“80 percent of the Children of two obese parents become obese，as compared with no more than 14 percent of the offspring of two parents of normal weight．” How can obese people become normal or even thin through dieting? Well，dieting can be effective．but the health costs are tremendous．Jules Hirsch，a research physician at Rockefeller University, did a study of eight fat people．They were given a liquid formula providing 600 calories a day1.After more than 10 weeks，the subjects lost 45kg on average．（第3题答案相关句）But after leaving the hospital，they all regained．The results were surprising：by metabolic measurement，fat people who lost large amounts of weight seemed like they were starving．They had psychiatric problems. They dreamed of food or breaking their diet2.They were anxious and depressed；some were suicidal．They hid food in their rooms．Researchers warn that it is possible that weight reduction doesn’t result in normal weight，but in an abnormal state resembling that of starved non-obese people． （第4段）Thin people，however, suffer from the opposite：They have to make a great effort to gain weight．Ethan Sims（问题句中的特征词），of the University of Vermont，got（说服，使, 变成， 获得） prisoners（犯人） to volunteer to （自愿）gain weight（与选项B中的细节信息结构呼应）．In four to six months，they ate as much as they could（尽可能地...）．They succeeded in （成功地）increasing their weight（与选项B中的细节信息结构呼应） by（了） 20 to 25 percent. But months after the study ended，they were back to normal weight and stayed there. （第5段）This did not mean that people are completely without hope in controlling their weight．It means that those who tend to be fat will have to constantly battle their genetic inheritance （选项A中的细节信息结构）if they want to significantly lower their weight（与选项D中的细节信息结构呼应）． 第4段中的答案相关句说：让犯人自愿增加体重。可见B是正确的答案。