北京新航道托福频道为考生提供托福TPO综合写作范文，让考生对照范文和题目好好研究分析，总结经验教训，不断自身的写作能力。下面请看TPO10的部分。

　　TPO 10

　　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.

　　上文就是此次小编为大家提供的TPO10托福综合写作范文，希望对同学们有所帮助。在范文的引导之下，不断改进。写出的文章来，加油!

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