閱讀材料：

　　The cane toad is a large (1.8 kg) amphibian species native to Central and South America. It was deliberately introduced to Australia in 1935 with the expectation that it would protect farmers crops by eating harmful insects. Unfortunately, the toad multiplied rapidly, and a large cane toad population now threatens small native animals that are not pest. Several measures have been proposed to stop the spread of the cane toad in Australia.

　　蔗蜍是一種原產于中南美洲的兩棲動物，個頭很大，重大1.8公斤。蔗蜍是在1935年由人工引進至澳大利亞的。因為它們可以吃害蟲，所以希望借由它們保護農作物。不幸的是，蔗蜍繁殖迅速。而且，數量巨大的蔗蜍群體已經開始威脅一些對農業無害的小型本土生物。現在提出了幾個解決蔗蜍在澳大利亞蔓延的方法。

　　One way to prevent the spread of the toad would be to build a national fence. A fence that blocks the advance of the toads will prevent them from moving into those parts of Australia that they have not yet colonized. This approach has been used before: a national fence was erected in the early part of the twentieth century to prevent the spread of rabbits, another animal species that was introduced in Australia from abroad and had a harmful impact on its native ecosystems.

　　第一個阻止蔗蜍蔓延的方法是建立一個全國范圍的圍欄。用圍欄控制蔗蜍增長的方式是通過阻止它們遷徙實現的，這樣它們就不會聚集到那些尚未被它們控制的地區了。這種方法以前就用過。在二十世界初期，澳大利亞就從用這種圍欄阻止兔子的過度增長。兔子由澳大利亞從他國引進后，給當地的生態平衡造成了巨大的災難。

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

　　第二，可以招募志愿者抓蔗蜍。簡單的陷阱就可以抓到蔗蜍，甚至徒手都可以抓到。至于蝌蚪和卵因為是生活在水里的，更是容易抓到和消滅。如果澳大利亞政府組織一個由澳大利亞公民參與的運動去消滅蔗蜍，那么可能會達到阻礙其蔓延的目的。

　　Third, researchers are developing a disease-causing virus to control the cane toad populations. This virus will be specially designed: although it will be able to infect a number of reptile and amphibian species, it will not harm most of the infected species; it will specifically harm only the cane toads. The virus will control the population of cane toads by preventing them from maturing and reproducing.

　　第三，研究人員正在研究一種用于控制蔗蜍數量的致病病毒。這種病毒是專門為控制蔗蜍研制的。盡管這種病毒也可以感染相當多數量的爬行動物和兩棲動物，但是這種感染基本是無害的。它只會影響蔗蜍。這種病毒通過阻礙蔗蜍的蔗蜍的成熟和繁殖實現控制其數量的目的。

　　閱讀部分需要提取的觀點是：

　　- Main point: 提供了三個控制蔗蜍數量的方法

　　- Sub point 1: 建立全國范圍性的圍欄

　　- Sub point 2: 組織志愿者抓

　　- Sub point 3: 研制某種特殊病毒，阻礙蔗蜍的成熟和繁殖

　　聽力材料：

　　The cane toad wont be as easy to get rid of as the reading suggests. The measures proposed by the reading are likely either to be unsuccessful or to cause unwanted environmental damage.

　　蔗蜍不會像閱讀部分說的那么容易出去的。閱讀部分提供的觀點不但是不會奏效，甚至會對環境造成損害。

　　First of all, a national fence probably wont stop the spread of the toad. Thats because young toads and toad eggs are found in rivers and streams. No matter where the fence is located, at some point there will be rivers or steams flowing from one side to the other. These waterways will be able to carry the young toads and their eggs to the other side. Since its only necessary for a few young toads or eggs to get though the fence in order to establish population on the other side, the fence is unlikely to be effective.

　　首先，一個全國范圍內的圍欄不會阻止蔗蜍的蔓延。這是因為蝌蚪和蔗蜍卵是生活在河水和溪流中的。不管圍欄怎么安排，總會有跨過河流和小溪的地方。在這些地方，流水可以越過圍欄。蝌蚪和蔗蜍卵可以通過這些水流穿過圍欄。只要有很小數量的蝌蚪和蔗蜍穿過圍欄，它們就可以建立起一個種群。所以，這種圍欄的方法是無效的。

　　Secondly, a massive group of volunteers could have success trapping and destroying toads. But its likely that these untrained volunteers would inadvertently destroy many of Australias native frogs some of which are endangered. Its not always easy to tell the cane toad apart from native frogs especially when its young.

　　第二，人數眾多的志愿者隊伍的確可以抓住和消滅蔗蜍。但是這些沒有經過訓練的志愿者很可能會無意間殺死很多澳大利亞原產的青蛙，而其中的一些已經是瀕危物種的。蔗蜍和澳大利亞原產青蛙并不容易區分，尤其是在它們都是幼體的時候。

　　Third, using the virus is a bad idea because it could have terrible consequences for cane toads in their original habitat in Central and South America. You might be wondering how can virus released in Australia cause harm in the Americas. Well, Australian reptiles and amphibians are often transported to other continents by researchers or pet collectors for example. Once the animals infected by the virus reach Central and South American, the virus will attack the native cane toads and devastate their populations. That would be an ecological disaster because in the Americans cane toads are a native species and a vital part of the ecosystem. So if they are eliminated the whole ecosystem will suffer.

　　第三，病毒可能會對蔗蜍原產的中南美洲的生態環境造成嚴重的破壞，所以使用病毒也是一個壞主意。你們可能很好奇為什么投放在澳大利亞的病毒會破換美洲的環境。恩，研究者或者寵物飼養者常常會被澳大利亞的爬行動物和兩棲類動物帶到其他的大洲。一旦感染此病毒的動物被帶到了中南美洲，那么這種病毒就會感染當地的蔗蜍，使得其數量銳減。因為蔗蜍在美洲是原生物種，是生態系統的重要組成部分，所以其數量銳減將會是生態災難。所以，如果蔗蜍滅絕了，那么美洲的生態系統也會受到破壞。

　　聽力部分需要提取的觀點是：

　　- Main point: 三個方法是無效甚至只有害的

　　- Sub point 1: 蔗蜍的蝌蚪和卵可以通過流水穿過圍欄，方法無效

　　- Sub point 2: 盡管志愿者可以抓到蔗蜍，但是可能會錯抓當地瀕危的原產青蛙

　　- Sub point 3: 使用病毒可能會破壞蔗蜍原產地中南美洲的生態平衡

　　閱讀材料：

　　The cane toad is a large (1.8 kg) amphibian species native to Central and South America. It was deliberately introduced to Australia in 1935 with the expectation that it would protect farmers crops by eating harmful insects. Unfortunately, the toad multiplied rapidly, and a large cane toad population now threatens small native animals that are not pest. Several measures have been proposed to stop the spread of the cane toad in Australia.

　　蔗蜍是一種原產于中南美洲的兩棲動物，個頭很大，重大1.8公斤。蔗蜍是在1935年由人工引進至澳大利亞的。因為它們可以吃害蟲，所以希望借由它們保護農作物。不幸的是，蔗蜍繁殖迅速。而且，數量巨大的蔗蜍群體已經開始威脅一些對農業無害的小型本土生物。現在提出了幾個解決蔗蜍在澳大利亞蔓延的方法。

　　One way to prevent the spread of the toad would be to build a national fence. A fence that blocks the advance of the toads will prevent them from moving into those parts of Australia that they have not yet colonized. This approach has been used before: a national fence was erected in the early part of the twentieth century to prevent the spread of rabbits, another animal species that was introduced in Australia from abroad and had a harmful impact on its native ecosystems.

　　第一個阻止蔗蜍蔓延的方法是建立一個全國范圍的圍欄。用圍欄控制蔗蜍增長的方式是通過阻止它們遷徙實現的，這樣它們就不會聚集到那些尚未被它們控制的地區了。這種方法以前就用過。在二十世界初期，澳大利亞就從用這種圍欄阻止兔子的過度增長。兔子由澳大利亞從他國引進后，給當地的生態平衡造成了巨大的災難。

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

　　第二，可以招募志愿者抓蔗蜍。簡單的陷阱就可以抓到蔗蜍，甚至徒手都可以抓到。至于蝌蚪和卵因為是生活在水里的，更是容易抓到和消滅。如果澳大利亞政府組織一個由澳大利亞公民參與的運動去消滅蔗蜍，那么可能會達到阻礙其蔓延的目的。

　　Third, researchers are developing a disease-causing virus to control the cane toad populations. This virus will be specially designed: although it will be able to infect a number of reptile and amphibian species, it will not harm most of the infected species; it will specifically harm only the cane toads. The virus will control the population of cane toads by preventing them from maturing and reproducing.

　　第三，研究人員正在研究一種用于控制蔗蜍數量的致病病毒。這種病毒是專門為控制蔗蜍研制的。盡管這種病毒也可以感染相當多數量的爬行動物和兩棲動物，但是這種感染基本是無害的。它只會影響蔗蜍。這種病毒通過阻礙蔗蜍的蔗蜍的成熟和繁殖實現控制其數量的目的。

　　閱讀部分需要提取的觀點是：

　　- Main point: 提供了三個控制蔗蜍數量的方法

　　- Sub point 1: 建立全國范圍性的圍欄

　　- Sub point 2: 組織志愿者抓

　　- Sub point 3: 研制某種特殊病毒，阻礙蔗蜍的成熟和繁殖

　　聽力材料：

　　The cane toad wont be as easy to get rid of as the reading suggests. The measures proposed by the reading are likely either to be unsuccessful or to cause unwanted environmental damage.

　　蔗蜍不會像閱讀部分說的那么容易出去的。閱讀部分提供的觀點不但是不會奏效，甚至會對環境造成損害。

　　First of all, a national fence probably wont stop the spread of the toad. Thats because young toads and toad eggs are found in rivers and streams. No matter where the fence is located, at some point there will be rivers or steams flowing from one side to the other. These waterways will be able to carry the young toads and their eggs to the other side. Since its only necessary for a few young toads or eggs to get though the fence in order to establish population on the other side, the fence is unlikely to be effective.

　　首先，一個全國范圍內的圍欄不會阻止蔗蜍的蔓延。這是因為蝌蚪和蔗蜍卵是生活在河水和溪流中的。不管圍欄怎么安排，總會有跨過河流和小溪的地方。在這些地方，流水可以越過圍欄。蝌蚪和蔗蜍卵可以通過這些水流穿過圍欄。只要有很小數量的蝌蚪和蔗蜍穿過圍欄，它們就可以建立起一個種群。所以，這種圍欄的方法是無效的。

　　Secondly, a massive group of volunteers could have success trapping and destroying toads. But its likely that these untrained volunteers would inadvertently destroy many of Australias native frogs some of which are endangered. Its not always easy to tell the cane toad apart from native frogs especially when its young.

　　第二，人數眾多的志愿者隊伍的確可以抓住和消滅蔗蜍。但是這些沒有經過訓練的志愿者很可能會無意間殺死很多澳大利亞原產的青蛙，而其中的一些已經是瀕危物種的。蔗蜍和澳大利亞原產青蛙并不容易區分，尤其是在它們都是幼體的時候。

　　Third, using the virus is a bad idea because it could have terrible consequences for cane toads in their original habitat in Central and South America. You might be wondering how can virus released in Australia cause harm in the Americas. Well, Australian reptiles and amphibians are often transported to other continents by researchers or pet collectors for example. Once the animals infected by the virus reach Central and South American, the virus will attack the native cane toads and devastate their populations. That would be an ecological disaster because in the Americans cane toads are a native species and a vital part of the ecosystem. So if they are eliminated the whole ecosystem will suffer.

　　第三，病毒可能會對蔗蜍原產的中南美洲的生態環境造成嚴重的破壞，所以使用病毒也是一個壞主意。你們可能很好奇為什么投放在澳大利亞的病毒會破換美洲的環境。恩，研究者或者寵物飼養者常常會被澳大利亞的爬行動物和兩棲類動物帶到其他的大洲。一旦感染此病毒的動物被帶到了中南美洲，那么這種病毒就會感染當地的蔗蜍，使得其數量銳減。因為蔗蜍在美洲是原生物種，是生態系統的重要組成部分，所以其數量銳減將會是生態災難。所以，如果蔗蜍滅絕了，那么美洲的生態系統也會受到破壞。

　　聽力部分需要提取的觀點是：

　　- Main point: 三個方法是無效甚至只有害的

　　- Sub point 1: 蔗蜍的蝌蚪和卵可以通過流水穿過圍欄，方法無效

　　- Sub point 2: 盡管志愿者可以抓到蔗蜍，但是可能會錯抓當地瀕危的原產青蛙

　　- Sub point 3: 使用病毒可能會破壞蔗蜍原產地中南美洲的生態平衡