Argument150 同主题习作

justinweiUID: 2234137

题目：ARGUMENT150 - The following is a letter to the editor of an environmental magazine.

"The decline in the numbers of amphibians worldwide clearly indicates the global pollution of water and air. Two studies of amphibians in Yosemite National Park in California confirm my conclusion. In 1915 there were seven species of amphibians in the park, and there were abundant numbers of each species. However, in 1992 there were only four species of amphibians observed in the park, and the numbers of each species were drastically reduced. The decline in Yosemite has been blamed on the introduction of trout into the park's waters, which began in 1920 (trout are known to eat amphibian eggs). But the introduction of trout cannot be the real reason for the Yosemite decline because it does not explain the worldwide decline."
字数：364          用时：00:30:00          日期：2008-3-1 17:15:37

The notion that global pollution of water and air results in decrease in number of amphibians sounds appealing at first glance. After all, pollution account for extinctions of some species. However, the argument would conceal other causes of decrease, potentially more significant.

To begin with, decreasing number observed can not deduce amphibians disappearing. Perhaps people failed to observe some of them still living there. Some amphibians were likely to transfer to other places for enough food available away from where they often show themselves. As a result, these individuals would go beyond the reach of observers for the time being in 1992. If, however, people would enlarge their scope of search and observation, it would be likely that those amphibians lost would appear again.

Second, it is not convincing to rule out introduction of trout as a probable alternative. The reason given for the exclusion is that introduction cannot yet explain decline in the whole world. Obviously, the arguer fails to realize the importance of balance in ecosystem, in which one species is dependent on and also limited by another. So it is possible that in other places except for Yosemite National Park, there is a certain specie as enemy to trout. If so, introduction of trout there would lead to less severe problems than in Yosemite, where enemies of trout never existed probably.

In addition, even if the argument could provide credible evidence to rule out the possibility of introduction of trout, it should not take it for granted that global pollution is responsible for decline worldwide, because other factors would be predominant in explaining the decline in some case. Perhaps most amphibians have become extinct because of unpredictable changes in climate, such as sharp decrease in temperature, which was out of what they could bear. Or maybe there was a fatal disease spread among them only having nothing to do with humans. So there are still quite a few significant alternatives requiring consideration.

The argument would render useful information researching decline of amphibians. Before any conclusions about blame or restrictions on pollution are reached, however, a more thorough research is needed. After all, a false assertion would lead to unwanted and inefficient measures.

风中尘埃UID: 164965

The notion that global pollution of water and air results in decrease in number of amphibians sounds appealing at first glance. After all, pollution account for extinctions of some species. However, the argument would conceal other causes of decrease, potentially more significant.[第一段的让步写的不错，可以学习下]

To begin with, decreasing number observed can not deduce amphibians disappearing.[这句用个从句吧，deduce that a is disappearing可能比较好] Perhaps people failed to observe some of them still living there. [这段你其实想说两个可能吧，一个是没看到，另一个是搬走？还是你只想说搬走了？反正这句比较奇怪]Some amphibians were likely to transfer to other places for enough food available away from where they often show themselves. As a result, these individuals would go beyond the reach of observers for the time being in 1992. If, however, people would enlarge their scope of search and observation, it would be likely that those amphibians lost would appear again.

Second, it is not convincing to rule out introduction of trout as a probable alternative. The reason given for the exclusion is that introduction cannot yet explain decline in the whole world. Obviously, the arguer fails to realize the importance of balance in ecosystem, in which one species is dependent on and also limited by another. So it is possible that in other places except for Yosemite National Park, there is a certain specie as enemy to trout. If so, introduction of trout there would lead to less severe problems than in Yosemite, where enemies of trout never existed probably.[你要证t鱼可能是原因，攻击点不是最容易想到的别的地方也有t鱼只是没被讨论，而是别的地方可能有t鱼的天敌，导致他们不会泛滥。这样我觉得也行，但是这个因果链比较长，最后在总结下回到主论点可能比较清晰。]

In addition, even if the argument could provide credible evidence to rule out the possibility of introduction of trout, it should not take it for granted that global pollution is responsible for decline worldwide, because other factors would be predominant in explaining the decline in some case. Perhaps most amphibians have become extinct because of unpredictable changes in climate, such as sharp decrease in temperature, which was out of what they could bear. Or maybe there was a fatal disease spread among them only having nothing to do with humans[pollution？为什么说human呢]. So there are still quite a few significant alternatives requiring consideration.

The argument would render useful information researching decline of amphibians. Before any conclusions about blame or restrictions on pollution are reached, however, a more thorough research is needed. After all, a false assertion would lead to unwanted and inefficient measures.

[思路很清晰，赞一个，要好好学习]
[如果可以的话，帮我看看吧，刚开始写，还没上路]