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2017年托福写作范文精选集(2)
亚洲的一种蛇头鱼(snakehead fish)被引入北美，对北美的生态系统产生威胁。有几种方法可以阻止蛇头鱼在北美的扩张。
第一种方法是：制定法律。鱼市的人经常把卖剩下的鱼倒入北美的河流湖泊中。只要制定法律限制这种行为便可阻止非本土的蛇头鱼对北美的生态环境造成危害。
第二种方法是：让北美的人了解到蛇头鱼是可以食用的。在亚洲，蛇头鱼是餐桌上的一道美食。而在北美，几乎没人食用蛇头鱼。所以，只要让北美的人了解到蛇头鱼是一道美食，渔民们便会开始大量捕杀它们，最终减少它们的数量。
第三种方法是：毒死那河流里的蛇头鱼。虽然这些有毒物质不仅仅会毒死蛇头鱼还会毒死本土的一些鱼种，但是可以重新在这些水域养殖本土的鱼种。
听力主要观点提取：
阅读中提到的每一种方法都不能保护美国的生态系统。
制定法律阻止人为将蛇头鱼引入北美并没用。因为蛇头鱼可以完全依靠自己从一个河流转移到另一条河流。
让渔民知道蛇头鱼是一道美食会适得其反。因为，当渔民知道卖蛇头鱼可以挣钱，他们会想法设法在更多水域养殖这种鱼，以便能够捕获更多数量。所以，蛇头鱼的数量不会下降。
毒死蛇头鱼然后再重新养殖本土鱼种不是一个好主意。因为有毒物质不仅仅会毒死河流里的鱼，还会毒死一些小的生物，如昆虫和两栖动物(amphibian)。这些生物一旦被毒死就无法恢复。然而，很多本土的鱼种以这些生物为食。所以，这种方法会导致之后重新养殖在湖泊里的本土鱼没有食物，数量会下降。
最新托福写作范文：
The writer puts forward three methods to stopping the spread of snakeheads in North America. Nevertheless, the professor demonstrates that none of the methods are likely to protect North America ecosystem.
First, in terms of making it illegal to transport and release snakeheads, the professor states that the snakeheads can spread to new waterways by themselves even without human’s transporting them. The reason is that snakeheads are able to live and move on land as long as they remain moist. So they can stay wet to reach a new lake or river.
Second, different from the belief in the reading that educating the fishers about snakeheads would reduce snakeheads’ population, the professor points out that it could end up with spreading snakeheads not reducing their number. When the fishers see the benefit to catch snakeheads, they would intentionally to introduce them to other lakes or rivers, even it is illegal. By dong this, they could catch more snakeheads and earn more money.
Finally, the professor contradicts the reading by saying that poisoning and restocking lakes or ponds is not a good idea. That’s because poisoning not only just kill snakeheads and other fishes, but also kill many small organisms, such as insects and amphibians which are the food source of native fishes. What’s more, these small organisms can not recover after being poisoned. As a result, it is not easy to restore the ecosystem by using poisoning.
