Car manufacturers and governments havebeen eagerly seeking a replacement for the automobile's main source of power,the internal-combustion engine. By far the most promising alternative source ofenergy for cars is the hydrogen-based fuel-cell engine, which uses hydrogen tocreate electricity that, in turn, powers the car. Fuel-cell engines haveseveral advantages over internal-combustion engines and will probably soonreplace them.(开头段)
One of the main problems with theinternal-combustion engine is that it relies on petroleum, either in the formof gasoline or diesel fuel. Petroleum is a finite resource; someday, we willrun out of oil. The hydrogen needed for fuel-cell engines cannot easily bedepleted. Hydrogen can be derived from various plentiful sources, includingnatural gas and even water. The fact that fuel-cell engines utilize easilyavailable, renewable resources makes them particularly attractive.(主体段1)
Fuel-cell-engines have several advantages overinternal-combustion engines, 然后三个主体段落分别展开说明。
以上列举了这个阅读文章的开头段和主体段1, 笔者在平时的教学中发现学生在看完阅读文章后，并没有真正理解文章的行文风格：fuel-cell engine和internal-combustion engine在全文中进行对比论证，正是由于没有理解这层关系，学生就按照惯例认为主体段第一句话是文章的中心，误认为中心句是：One of the mainproblems with the internal-combustion engine is that it relies on petroleum,either in the form of gasoline or diesel fuel.
然后学生就开始记听力笔记，大致内容是：be not easilyavailable, store in an extremely surrounding, minus 253 degrees centigrade…
这个段落真正的主题句应该是：The hydrogenneeded for fuel-cell engines cannot easily be depleted, 这样根据刚才的听力笔记的关键词来看阅读和听力材料的具体内容才是一一对应的。
One theory holds that the Chaco structures were purelyresidential, with each housing hundreds of people. Supporters of this theoryhave interpreted Chaco great houses as earlier versions of the architectureseen in more recent Southwest societies. In particular, the Chaco houses appearstrikingly similar to the large, well-known "apartment buildings" atTaos, New Mexico, in which many people have been living for centuries.(阅读材料)
这篇阅读文章的分论点一的内容是：One theory holds that the Chacostructures were purely residential, with each housing hundreds of people. 而在这个段落所对应的听力细节关键词就是：fewer fireplaces/ not enoughfor 100 people…。在书写过程中运用好转折关系就使得综合写作段落组织有序，衔接紧密，有很强的逻辑性。那么这个段落书写如下：The reading passage says that such housing structurewas applied for residence, with each housing hundreds of people. On the otherhand, the lecturer believes that there were fewer fireplaces providing forpeople application, let alone satisfying more than 100 people.
在独立作文中对逻辑性也有相关的要求：考生在提出论点之后，必须寻找相关的例证来支持和充实自己的论点。需要强调的是，在托福考试中考生可以发散地进行说理和寻找例证，但若是将自己所举的例证进行一定加工，按照由主到次、让步转折等顺序进行排列，则能更好地显示出各个例证之间的逻辑关系，让举例或是说理论证的过程更有层次性，这样的文章才称得上well-organized and well-developed. 以下面一个考题为例：
Do you agree or disagree with the following statement: Improvingeducation is the most important thing in the development of a country.(题目)
Secondly, improving education seems to regulate the quality ofpopulation, which in turn promotes a favorable civilization. For instance,because of the lack of quality-oriented education, most students nowadaysalways perform badly, including showing no respect to elders, dropping litterhere and there, and particularly arguing with others for simple things. Worsemore, increasing number of news appears that the rate of teenage crime isrising up rapidly. If the education system is not regulated, the monolithicimage will be destroyed, and will induce some negative impact to a country’sdevelopment. It turned that, education is playing an important andindispensible role in the development of a country.(考生文章1)
Secondly, improving education will improvethe level of quality and makes the country become a civilization state. Takethe example of the National University of Singapore; it has a strict teachingmanagement system. At school, many people will take punishments because of alittle thing like spiting and throwing garbage anywhere. To a certain degree,people will realize that a school is society in miniature. Gradually, theirlevels of quality will be higher and higher not only in a school but also in acountry. So, the Singapore is known for its civilization. To sum up, theeducation has the most important effect on a country.(考生文章2)