听力材料Well, ongoing investigations have revealed that predation is the most likely cause of sea otter decline after all.目前的研究表明天敌捕食是最可能导致海獭数量减少的
阅读材料：Car manufacturers and governments have been eagerly seeking a replacement for the automobile’s main source of power, the internal-combustion engine. By far, the most promising alt
听力材料：The reading is correct in pointing out the problems associated with oil-powered cars. Yes, oil is a finite resource, and yes, burning oil harms the environment. However, the reading is
阅读材料：Toward the end of his life, the Chevalier de Seingalt (1725-1798) wrote a long memoir recounting his life and adventures. The Chevalier was a somewhat controversial figure, but since he
听力材料：No memoir can possibly be correct in every detail, but still, the Chevalier’s memoir is pretty accurate overall, and is, by and large, a reliable historical source. Let’s lo
阅读材料：In an effort to encourage ecologically sustainable forestry practices, an international organization started issuing certifications to wood companies that meet high ecological standards
听力材料Well, despite what many people say, there is good reason to think that many American wood companies will eventually seek ecocertification for their wood products.尽管有很多人那么
阅读材料：Communal online encyclopedias represent one of the latest resources to be found on the Internet. They are in many respects like traditional printed encyciopedias, however, is that any i
听力材料The communal online encyclopedia will probably never be perfect, but that's a small price to pay for what it does offer. The criticisms in the reading are largely the result of prejudice a
21. Do you agree or disagree with the following statement? Face-to-face communication is better than other types of communication, such as letters, email, or telephone calls.22. Some people like to do