263. Case histories show that all nations face recurring periods of economic fluctuations .

　　案例记录表明：所有国家都面临循环出现的经济波动期。

　　264. Personal experience leads me to conclude that all people need to take time to smell the roses ( evaluate and appreciate the many good things they have in their lives ) .

　　个人经验使我得出这样的结论：所有人都需要有时间放松(评价并欣赏他们生活中许多美好的事物)。

　　265. Recent studies conducted by doctors show that excessive exposure to the sun's rays causes skin cancer .

　　最近医生所做的研究表明：过度暴露在阳光下会致癌。

　　266. Nationwide surveys conducted in 1997 revealed a dramatic rise in the ownership of television sets , refrigerators , air conditioners and washing machines .

　　1997年所做的全国范围内的调查显示电视机、电冰箱、空调和洗衣机拥有量大幅升高。

　　267. History tells us that mankind has a tendency to repeat past mistakes .

　　历史告诉我们人类有重蹈覆辙的趋势。

　　268. We have amassed ample objective proof to show the urgent need for crisis intervention in suspected child abuse cases .

　　我们已经积累了充足的客观证据证明急需干涉可疑的虐待儿童的案件。

　　269. Unfortunately , available evidence fails to establish any direct link between smoking and cancer .

　　不幸的是，现有的证据不能证明抽烟和癌症之间有直接的联系。

　　270. Fortunately , mountains of reliable evidence proves the direct link between smoking and cancer beyond any shadow of the doubt .

　　庆幸的是，大量可靠的证据证明抽烟和癌症有直接联系是毫无疑问的。

　　271. Television violence has contributed directly to rising crime , as evidenced by statistics showing a dramatic rise in copycat crimes .

　　数据显示模仿的犯罪行为有大幅度的增加，这证明电视暴力是犯罪增加的一部分直接原因。

　　272. The introduction of adcance agronomic techniques has contributed greatly to the development of agriculture , as indicated by statistics showing increased output in each of the past five years .

　　数据显示在过去的五年中，每一年的产量都有提高，这表明发达的农业技术的引入对农业发展起到了很大的作用。

　　273. While it may appear that the gap between rich and poor people is narrowing somewhat , recently released evidence suggests that the opposite is true .

　　贫富之间的差距看似有一定的缩小，但是最近发布的证据表明事实正好相反。

　　274. While attaining world peace remains within the realm of possibility , the prevailing trend revolves around regional conflicts and internal strife in many countries .

　　获得世界和平是有可能的，但是普遍的趋势是存在地区冲突和许多国家内部的斗争。

　　275. Although statistics are quite often far less reliable than one might wish , other reliable information allows one to closely approximate industrial output figures .

　　尽管数据经常比人们希望的不可靠得多，但是，其他可靠的信息使人们能得到接近工业产量的数字。

　　276. Although random sampling used for many surveys fails to cover large segments of the population , the procedure nonetheless offers insight into voting and consumption patterns .英语作文
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