托福综合写作优秀作文练习题：为何阻止蔗蜍蔓延

 　　托福综合写作阅读材料：

　　The cane¹ toad² is a large (1.8 kg) amphibianspecies native to Central and South America. It was deliberately³ introduced toAustralia in 1935 with the expectation that it would protect farmers’ crops byeating harmful insects. Unfortunately, the toad multiplied rapidly, and a largecane toad population now threatens small native animals that are not pest.Several measures have been proposed to stop the spread of the cane toad inAustralia.

　　蔗蜍是一种原产于中南美洲的两栖动物，个头很大，重大1.8公斤。蔗蜍是在1935年由人工引进至澳大利亚的。因为它们可以吃害虫，所以希望借由它们保护农作物。不幸的是，蔗蜍繁殖迅速。而且，数量巨大的蔗蜍群体已经开始威胁一些对农业无害的小型本土生物。现在提出了几个解决蔗蜍在澳大利亚蔓延的方法。

　　One way to prevent the spread of the toadwould be to build a national fence. A fence that blocks the advance of thetoads will prevent them from moving into those parts of Australia that they havenot yet colonized⁵. This approach has been used before: a national fence waserected in the early part of the twentieth century to prevent the spread ofrabbits, another animal species that was introduced in Australia from abroadand had a harmful impact on its native ecosystems⁷.

　　第一个阻止蔗蜍蔓延的方法是建立一个全国范围的围栏。用围栏控制蔗蜍增长的方式是通过阻止它们迁徙实现的，这样它们就不会聚集到那些尚未被它们控制的地区了。这种方法以前就用过。在二十世界初期，澳大利亚就从用这种围栏阻止兔子的过度增长。兔子由澳大利亚从他国引进后，给当地的生态平衡造成了巨大的灾难。

　　Second, the toads⁴ could be captured anddestroyed by volunteers. Cane toads can easily be caught in simple traps andcan even be captured by hand. Young toads and cane toad eggs are even easier togather and destroy, since they are restricted tothe water. If the Australiangovernment were to organize a campaign among Australian citizens to join forcesto destroy the toads, the collective effort might stop the toad from spreading.

　　第二，可以招募志愿者抓蔗蜍。简单的陷阱就可以抓到蔗蜍，甚至徒手都可以抓到。至于蝌蚪和卵因为是生活在水里的，更是容易抓到和消灭。如果澳大利亚政府组织一个由澳大利亚公民参与的运动去消灭蔗蜍，那么可能会达到阻碍其蔓延的目的。

　　Third, researchers are developing adisease-causing virus to control the cane toad populations. This virus will bespecially designed: although it will be able to infect a number of reptile⁸ and amphibianspecies, it will not harm most of the infected species; it will specificallyharm only the cane toads. The virus will control the population of cane toadsby preventing them from maturing and reproducing.

　　第三，研究人员正在研究一种用于控制蔗蜍数量的致病病毒。这种病毒是专门为控制蔗蜍研制的。尽管这种病毒也可以感染相当多数量的爬行动物和两栖动物，但是这种感染基本是无害的。它只会影响蔗蜍。这种病毒通过阻碍蔗蜍的蔗蜍的成熟和繁殖实现控制其数量的目的。

　　托福综合写作阅读部分需要提取的观点是：

　　- Main point: 提供了三个控制蔗蜍数量的方法

　　- Sub point 1: 建立全国范围性的围栏

　　- Sub point 2: 组织志愿者抓

　　- Sub point 3: 研制某种特殊病毒，阻碍蔗蜍的成熟和繁殖

　　托福综合写作听力材料：

　　The cane toad won’t be as easy to get ridof as the reading suggests. The measures proposed by the reading are likelyeither to be unsuccessful or to cause unwanted environmental damage.

　　蔗蜍不会像阅读部分说的那么容易出去的。阅读部分提供的观点不但是不会奏效，甚至会对

　　环境造成损害。

　　First of all, a national fence probablywon’t stop the spread of the toad. That’s because young toads and toad eggs arefound in rivers and streams. No matter where the fence is located, at some pointthere will be rivers or steams flowing from one side to the other. Thesewaterways will be able to carry the young toads and their eggs to the otherside. Since it’s only necessary for a few young toads or eggs to get though thefence in order to establish population on the other side, the fence is unlikelyto be effective.

　　首先，一个全国范围内的围栏不会阻止蔗蜍的蔓延。这是因为蝌蚪和蔗蜍卵是生活在河水和溪流中的。不管围栏怎么安排，总会有跨过河流和小溪的地方。在这些地方，流水可以越过围栏。蝌蚪和蔗蜍卵可以通过这些水流穿过围栏。只要有很小数量的蝌蚪和蔗蜍穿过围栏，它们就可以建立起一个种群。所以，这种围栏的方法是无效的。

　　Secondly⁹, a massive group of volunteers couldhave success trapping and destroying toads. But it’s likely that theseuntrained volunteers would inadvertently destroy many of Australia’s nativefrogs some of which are endangered. It’s not always easy to tell the canetoadapart from native frogs especially when it’s young.

　　第二，人数众多的志愿者队伍的确可以抓住和消灭蔗蜍。但是这些没有经过训练的志愿者很可能会无意间杀死很多澳大利亚原产的青蛙，而其中的一些已经是濒危物种的。蔗蜍和澳大利亚原产青蛙并不容易区分，尤其是在它们都是幼体的时候。

　　Third, using the virus is a bad ideabecause it could have terrible consequences for cane toads in their originalhabitat in Central and South America. You might be wondering how can virus releasedin Australia cause harm in the Americas. Well, Australian reptiles¹⁰ andamphibians are often transported to other continents by researchers or petcollectors for example. Once the animals infected by the virus reach Centraland South American, the virus will attack the native cane toads and devastatetheir populations. That would be an ecological¹¹ disaster because in the Americanscane toads are a native species and a vital part of the ecosystem⁶. So if theyare eliminated the whole ecosystem will suffer.

　　第三，病毒可能会对蔗蜍原产的中南美洲的生态环境造成严重的破坏，所以使用病毒也是一个坏主意。你们可能很好奇为什么投放在澳大利亚的病毒会破换美洲的环境。恩，研究者或者宠物饲养者常常会被澳大利亚的爬行动物和两栖类动物带到其他的大洲。一旦感染此病毒的动物被带到了中南美洲，那么这种病毒就会感染当地的蔗蜍，使得其数量锐减。因为蔗蜍在美洲是原生物种，是生态系统的重要组成部分，所以其数量锐减将会是生态灾难。所以，如果蔗蜍灭绝了，那么美洲的生态系统也会受到破坏。

　　托福综合写作听力笔记：

　　- Main point: 三个方法是无效甚至只有害的

　　- Sub point 1: 蔗蜍的蝌蚪和卵可以通过流水穿过围栏，方法无效

　　- Sub point 2: 尽管志愿者可以抓到蔗蜍，但是可能会错抓当地濒危的原产青蛙

　　- Sub point 3: 使用病毒可能会破坏蔗蜍原产地中南美洲的生态平衡

　　本篇范文可以借鉴的模板是：

　　The lecturer argues against the three measuresmentioned in the reading passage to _____________________.

　　The lecturer argues that the first measure,_______________________. The reading passage, however, argues that such a______would ______________.

　　Regarding the second measure,__________, thelecturer explains that ________________. The reading passage gives the oppositeview: ___________________.

　　Finally, the lecturer objects to the thirdmeasure—_______________. She points out that __________________. This is indirect contradiction with the claim in the reading passage that _____________________.

　　托福综合写作范文(仅供参考)：

　　The lecturer argues against the threemeasures mentioned in the reading passage to reduce the population of the canetoad, a species introduced to the Australian continent.

　　The lecturer argues that the first measure,a national fence, would not prevent the flow of streams or rivers and,therefore, would allow young toads or toad eggs to travel to the other side ofthe fence. The reading passage, however, argues that such a fence wouldeffectively cut off the route that animals use to establish colonies and expandin population.

　　Regarding the second measure, recruiting alarge group of volunteers, the lecturer explains that volunteers often havedifficulty distinguishing between cane toads and native frogs, an endangered species;therefore, they might kill members of both species. The reading passage givesthe opposite view: Organizing a large group of volunteers to join anextermination campaign would speed the destruction of cane toads.

　　Finally, the lecturer objects to the thirdmeasure—using an infectious virus. She points out that a virus intended toeliminate Australia’s cane toad population could be transmitted through animal transportationto other continents where cane toads are an essential part of the ecosystem.This is in direct contradiction with the claim in the reading passage that aninfectious virus could be developed to stop the reproduction of cane toadswithout harming other species.

1 cane   

n.手杖，细长的茎，藤条；v.以杖击，以藤编制的

参考例句：

• This sugar cane is quite a sweet and juicy.这甘蔗既甜又多汁。
• English schoolmasters used to cane the boys as a punishment.英国小学老师过去常用教鞭打男学生作为惩罚。

2 toad   

n.蟾蜍，癞蛤蟆

参考例句：

• Both the toad and frog are amphibian.蟾蜍和青蛙都是两栖动物。
• Many kinds of toad hibernate in winter.许多种蟾蜍在冬天都会冬眠。

3 deliberately   

adv.审慎地；蓄意地；故意地

参考例句：

• The girl gave the show away deliberately.女孩故意泄露秘密。
• They deliberately shifted off the argument.他们故意回避这个论点。

4 toads   

n.蟾蜍，癞蛤蟆( toad的名词复数 )

参考例句：

• All toads blink when they swallow. 所有的癞蛤蟆吞食东西时都会眨眼皮。 来自《简明英汉词典》
• Toads have shorter legs and are generally more clumsy than frogs. 蟾蜍比青蛙脚短，一般说来没有青蛙灵活。 来自辞典例句

5 colonized   

开拓殖民地，移民于殖民地( colonize的过去式和过去分词 )

参考例句：

• The area was colonized by the Vikings. 这一地区曾沦为维京人的殖民地。
• The British and French colonized the Americas. 英国人和法国人共同在美洲建立殖民地。

6 ecosystem   

n.生态系统

参考例句：

• This destroyed the ecosystem of the island.这样破坏了岛上的生态系统。
• We all have an interest in maintaining the integrity of the ecosystem.维持生态系统的完整是我们共同的利益。

7 ecosystems   

n.生态系统( ecosystem的名词复数 )

参考例句：

• There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
• Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样，从雨林到半荒漠等不一而足。 来自辞典例句

8 reptile   

n.爬行动物；两栖动物

参考例句：

• The frog is not a true reptile.青蛙并非真正的爬行动物。
• So you should not be surprised to see someone keep a reptile as a pet.所以，你不必惊奇有人养了一只爬行动物作为宠物。

9 secondly   

adv.第二，其次

参考例句：

• Secondly,use your own head and present your point of view.第二，动脑筋提出自己的见解。
• Secondly it is necessary to define the applied load.其次，需要确定所作用的载荷。

10 reptiles   

n.爬行动物，爬虫( reptile的名词复数 )

参考例句：

• Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
• Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》

11 ecological   

adj.生态的，生态学的

参考例句：

• The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
• Each animal has its ecological niche.每种动物都有自己的生态位.