托福写作难并不意味着不可能拿满分和，只要多努力，北京新航道托福频道推出托福综合写作范文15篇系列，和大家分享托福写作的一些满分、的文章。今天我们来看第7篇范文。

　　The lecturer and the reading passage suggest two competing theories, the predation theory vs. the pollution theory, to explain why the sea otter population is in rapid decline.

　　The professor reasons that the absence of dead sea otters washed up the coast suggests that their decline is not caused by sea pollution but rather by sea predators who consume their bodies after Killing them. In contrast, the reading passage attributes the death of sea otters to pollution, citing evidence of increased sources of ocean contaminants which lead to greater vulnerability to infections.

　　Furthermore, the lecturer argues that orcas are likely factors in the disappearance of sea otters, because the scarcity of whales, their usual prey, has left them with no other choice but to start hunting smaller mammals like the otters for food. 来源：北京新航道托福培训 The reading passage, on the other hand, Rules out this theory based on the orca’s preying habit, and instead approves of the pollution theory as the only explanation for the decline op both large and small sea mammals across the entire ecosystem.

　　Finally, according to the lecturer, the uneven pattern of sea otter decline corresponds to the distribution of the orcas. She argues that the pact that their population has declined most rapidly where orcas are most prevalent further validates the predation theory. However, the reading passage argues that changeable environmental factors, which lead to different concentrations of pollutants, better explains the varying pattern of sea otter decline.

　　上面就是托福综合写作范文15篇的第7篇范文，大家要认真地看，仔细的研究，透彻理解托福写作的行文布局，遣词造句，争取自己也拿到满分、!加油!

　　了解托福培训信息