2017年托福考试写作练习及精选范文(22)

>>托福写作：2017年托福考试写作练习及精选范文(22)

>>托福成绩提升方案

阅读主要观点提取：

总论点：新几内亚扁形虫flatworm通过植物上的泥土传播到欧洲，并对欧洲的动物造成巨大威胁。有三个方法可以控制它在欧洲的扩张。

分论点一：生物控制。一是可以在新几内亚找到这种扁形虫的捕食者来吃它;二是让欧洲本土的鸟或爬行动物吃它。

分论点二：化学控制。用一种不伤害其他动物的杀虫剂来消灭flatworm。

分论点三：土壤消毒。扁形虫生存在盆栽植物中，并且它不耐高温。所以只要将所有进口的盆栽植物在50摄氏度的水里过滤下，扁形虫就会被消灭。

听力主要观点提取：

总论点：每一种方法是无效的。

分论点一：一方面，这种扁形虫在新几内亚并没有任何捕食者。另一方面，欧洲本土的鸟类和爬行动物也不会吃它，因为它的肉是酸的，并不好吃。

分论点二：大部分杀虫剂都不能消灭新几内亚扁形虫。只有一种名为lindane的杀虫剂可以消灭它，但是同时还会消灭其他动物，所以使用这种杀虫剂得不偿失。

分论点三：土壤消毒不能消灭欧洲所有扁形虫。盆栽植物中有很多泥土，即使将盆栽植物倾倒出来，还有一部分依附在植物深处泥土中的扁形虫并不会被高温杀死。

学生满分范文：

The writer puts forward three methods to control the further spread of New Guinea flatworm. However, the professor demonstrates that none of the methods turns out to be successful.

First, as for the biological control, the professor contradicts the reading material. On the one hand, the New Guinea flatworm has no predator in its habitat. On the other hand, the local predators in Europe, like birds or reptiles, would not eat the flatworm because its meat tastes sour and unpleasant.

Second, the professor illustrates that the chemical control mentioned in the reading is ineffective. It is because that the New Guinea flatworm is resistant to most of pesticides. What’ more, the flatworm would be killed by one type of pesticide, lindane, which is very toxic for other species. So it is not worth to use lindane to kill flatworm.

Third, the writer points out that the spread of the flatworm could be prevented by properly sterilizing the soil pots. In contrast, the professor refutes the idea by saying that hot water may not destroy all flatworms. The reason is that flatworms’ older eggs are buried deep within the soil and tipping the pots will not allow the heat to kill the eggs in the deep soil. So they will escape the tip and survive.

更多关于托福的考试资讯、备考资料、学习技巧等内容尽在坦途网托福考试频道，欢迎了解关注。