Argumen 47 请拍！还有18天考试~请帮忙！

matcheaven~UID: 2597874

这是我第二篇a, 离考试还有18天， 我却完全不能按规定时间完成，今天写了1个小时也才写了200多字，写在这里不怕丢人，就是请各位高手出出主意，怎么才能提高呀？？十分着急！！
我写完了又用了一个多小时改了一遍，参考使徒斑斑以前给一个人改的A47，请大家看看。

最重要的还是怎么在规定时间完成呀？？怎么练习？
谢谢大家帮忙了！！

这个是我最开始写的，可以不看，二楼是我修改过的， 劳烦大家帮帮忙提提意见~


TOPIC: ARGUMENT47 - Scientists studying historical weather patterns have discovered that in the mid-sixth century, Earth suddenly became significantly cooler. Although few historical records survive from that time, some accounts found both in Asia and Europe mention a dimming of the sun and extremely cold temperatures. Either a huge volcanic eruption or a large meteorite colliding with Earth could have created a large dust cloud throughout Earth's atmosphere that would have been capable of blocking enough sunlight to lower global temperatures significantly. A large meteorite collision, however, would probably create a sudden bright flash of light, and no extant historical records of the time mention such a flash. Some surviving Asian historical records of the time, however, mention a loud boom that would be consistent with a volcanic eruption. Therefore, the cooling was probably caused by a volcanic eruption.
WORDS: 261
TIME: 01:00:00
DATE: 2009-9-6 11:47:17

The arguer concludes that the suddenly cooling in the mid-sixth century was probably caused by a volcanic eruption. To support this conclusion the arguer cites several reasons:1) some accounts mention a dimming of the sun and extremely cold temperatures; 2) this low temperature is caused by a large dust cloud which block enough sunlight ;3)either a huge volcanic eruption or a large meteorite colliding with Earth could have created that dust cloud; 4)there is no records of bright light but exist a record of a loud boom, thus the cooling is cause by a volcanic eruption. However, the series of reasons base on an unsubstantiated assumption, which make it unpersuasive as it stands.

First of all, the arguer's conclusion depends on the assumption that the historical records found in Asia and Europe are reliable. Yet, the arguer offers no evidence to substantiate this assumption. The

Secondly, it is too hasty to say that the either a huge volcanic eruption or a large meteorite colliding with Earth could have created that dust cloud that would have been capable of blocking enough sunlight to lower global temperatures. Other factors can also contribute to the cold temperatures.
Perhaps during that time the sun was much farer from the Earth than ever. Without ruling out other possibilities might also cause the cooling, it is hard to make us believe the author's conclusion.

Thirdly, the fact that no records about sudden bright flash have been discovered dose not indicate that there was no any meteorite collision at that time. Similarly, the loud boom mentioned by As

matcheaven~UID: 2597874

[b]修改
TOPIC: ARGUMENT47 - Scientists studying historical weather patterns have discovered that in the mid-sixth century, Earth suddenly became significantly cooler. Although few historical records survive from that time, some accounts found both in Asia and Europe mention a dimming of the sun and extremely cold temperatures. Either a huge volcanic eruption or a large meteorite colliding with Earth could have created a large dust cloud throughout Earth's atmosphere that would have been capable of blocking enough sunlight to lower global temperatures significantly. A large meteorite collision, however, would probably create a sudden bright flash of light, and no extant historical records of the time mention such a flash. Some surviving Asian historical records of the time, however, mention a loud boom that would be consistent with a volcanic eruption. Therefore, the cooling was probably caused by a volcanic eruption.

In this argument, the arguer concludes that the suddenly cooling in the mid-sixth century was probably caused by a volcanic eruption. To support this conclusion the arguer cites several reasons: 1) some accounts mention a dimming of the sun and extremely cold temperatures, and this dimming of the sun and low temperature were caused by a large dust cloud which block enough sunlight; 2) either a huge volcanic eruption or a large meteorite colliding with Earth could have created that dust cloud; 3) there is no records of bright light but exist a record of a loud boom, thus the cooling is cause by a volcanic eruption. However, the series of reasons base on an unsubstantiated assumption, which make it unpersuasive as it stands.

First of all, the arguer's conclusion depends on the assumption that the historical records found in Asia and Europe are reliable. Yet, the arguer offers no evidence to substantiate this assumption. In addition, the fact that few historical records survive from the mid-sixth century, as the author claims in the argument, tells us that it is unfair to make the conclusion merely based on those few records, because it is quite possible that many evidences leading a totally different result were fail to be recorded. Without showing that the records found in Asia and Europe can include all the atmosphere during that period of time, it is unpersuasive to conclude that the dimming of the sun is the reason for low temperature at that time, thus maybe there are other factors, rather than large dust cloud which block enough sunlight, could lead to the cold temperature.

Even the cold temperature due to the large dust cloud which blocking(语法：为啥不是block？？) enough sunlight, it is too hasty to say that either a huge volcanic eruption or a large meteorite colliding with Earth could have created that dust cloud. There are many other factors, such as severe earthquake, could also have contributed to such large dust cloud. Without carefully rule out other possibilities through a scientific method(有没有更好的表达？想不出来了~~), we cannot believe that there are merely two explanations for the formation of the large dust cloud.

Thirdly, even the dust clouds were created by either a huge volcanic eruption or a large meteorite colliding with Earth, the conclusion is still open to doubt. On one hand, the fact that no records about sudden bright flash of light have been discovered does not indicate that there was no any meteorite collision at that time. As the foregoing statement illustrated, maybe there indeed existed such sudden bright flash of light, but it was not recorded, because few historical records survive from the mid-sixth century. On the other hand, the loud boom mentioned by Asian historical records could be created by reasons other than volcanic eruption, for lacking of more solid evidence to build a causal relationship between the volcanic eruption and the loud boom. Thus, the evidence provided by the author is insufficient to demonstrate the conclusion that the suddenly cooling in the mid-sixth century was probably caused by a volcanic eruption.

In conclusion, the argument is based on a series unsubstantiated assumption, which makes it unpersuasive as it stands. To strengthen it the author must cite more solid evidences to substantiate his assumptions.

matcheaven~UID: 2597874

自己顶一个，大家帮忙~~！