20. The following appeared in an article in a health and fitness magazine. Laboratory studies show that Saluda Natural Spring Water contains several of the minerals necessary for good health and that it is completely free of bacteria. Residents of Saluda， the small town where the water is bottled， are hospitalized less frequently than the national average. Even though Saluda Natural Spring Water may seem expensive， drinking it instead of tap water is a wise investment in good health. Discuss how well reasoned.。. etc.
Sample essay 1：
The argument that drinking Saluda Natural Spring Water instead of tap water is a wise investment in good health is not entirely logically convincing， since it lacks certain supporting factors.
Firstly， the argument assumes that Saluda Natural Spring Water is the major reason why residents of Saluda are less frequently hospitalized than the national average. However， there is little evidence that this water is the only difference between this place and the rest of the country. And the reason why people in other places are more hospitalized are numerous and varied. There are so many other factors that would bring people in other places to hospitals， such as accidents， food contamination， illnesses， etc.
Secondly， the argument also assumes that the minerals in Saluda National Spring Water are the key minerals for the good health of the residents of Saluda. However， this may not be true. We need not only minerals to keep good heath but also various vitamins. Besides， our body needs more minerals than those contained in Saluda Natural Spring Water.
Finally， even if the Saluda water is the major reason why the residents of Saluda are less hospitalized， the argument still omits the fact that there is more than one way to keep drinking water free from bacteria. For instance， the most common practice is to boil water up to 100 degree Celsius and keep it at that degree for more than 5 minutes. Therefore drinking Saluda water to keep good health is not the only alternative.
Thus， the argument is not completely sound. The evidence in support of the conclusion that the Saluda residents are less hospitalized does little to prove the conclusion that drinking Saluda Natural Spring Water is a wise investment in good health since it omits the assumptions I have just raised. The argument might have been strengthened by making it plain that Saluda Natural Spring Water is the major reason why the residents of Saluda are less hospitalized， that the water contains all the major minerals essential for the human body， and that there is no other way to keep water from bacteria.
小编提醒：考生们可在日常生活中多读范文，多练笔，培养出好的语感和逻辑，这样才能在考试中写出优秀的作文。