TOEFL iBT阅读技巧—关键词法解题关键词在阅读理解中的重要作用：key words—结构（structure）—推断（inference）1.key words—结构（structure）针对题型：大意概括题解题步骤：1.找结构关键词（but, and, as ,while, so, to……）;2.分析句子结构; (并列，递进，从属，因果……)3.结合文本大意选出正确选项。
例1TPO34 Islamic Art and the BookPapermaking spread quickly to Egypt – and eventually to Sicily and Spain – but it was several centuries before paper supplanted parchment for copies of the Koran, probably because of the conservative nature of religious art and itspractitioners.Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.A) It was several centuries before papermaking techniques spread tofaraway areas where parchment was popular and used widely in art.B) Although papermaking came to Egypt quickly, it took much longer forpaper to be used when copying the Koran, probably because of the conservative nature of religious art.C) Papermaking spread beyond Egypt, Sicily, and Spain, but it was notwidely used by artists for centuries, probably because of the conservative nature of art in those countries.D) Paper replaced parchment in copies of the Koran, probably at therequest of conservative practitioners in areas like Egypt, Sicily, and Spain.[解析]关键词：but, because of. But 连接的是两个句子的转折，而because of 是对这种转折的原因的解释。
所以这个句子可以看成一个转折加上了一个因果解释。
即：快速传播，但是花了很久才取代，这样的原因是。
回到题干，答案的结构中应该包含转折和因果，马上排除A,D , C项信息超出了原文内容（注意beyond），排除，所以选B.例2TPO33 The First CivilizationsWhile some of these urban centerswere identified with a particular economic function, such as proximityto gold or irondeposits or a strategiclocation on a major traderoute,others served primarily asadministrativecenters or the site of templesforthe official cult or other ritual observances.Which of the sentences below bestexpresses the essentialinformation in thehighlightedsentence in the passage?Incorrect choices change the meaning inimportant ways or leave out essentialinformation.A)Some cities wereassociated with economic activities, while othersweregovernment or religious centers.B)Emerging citiesgenerallyservedstrategicadministrative,economic,andreligious purposes.C)The creation of an economic or administrative activity led to theemergenceof a city for its proper supervision.D)Some cities emerged aseconomic centers and later became the sitesofadministrative or religious activities.[解析]关键词: while,others对比关系，一些怎么样，而另一些怎么样，立即可以找出A选项，检查一下句子意思，符合原文，答案就是A.例3TPO 33 Extinction Episodes of the PastHowever, no group or species can maintain its dominance indefinitely,and when, after over200 million years, the age of dinosaurscame to a dramatic end about 65millionyearsago,mammals began to flourish, evolving fromrelativelyfew types ofsmallterrestrial animals into themyriad of diversespecies, including batsandwhales,that we knowtodayWhich of the sentences below best expresses the essential informationin the highlighted sentence in the passage? Incorrect choices changethe meaning in important ways or leave out essential information.A)The dominance of dinosaurs came to an end 65 million yearsago, at which time mammals began to flourish and diversify.B)Because no group of species can remain dominant forever,mammals became the dominant group when dinosaurs became extinct.C)After being the dominant group for more than 200 million years,the age of dinosaurs came to a dramatic end 65 million years ago.D)The diverse group of mammals that we know today, includingbats and whales, evolved from small terrestrial forms that had beendominated by dinosaurs.[解析]关键词: and when; 该句子有多个插入语和伴随状语，看似较复杂，其实抓住and when就很简单。
首先and是该句子两部分的并列，即第一句没有物种能够永远主宰以及when引导的时间状语从句。
而这两个部分是概括和具体的关系，when引导的从句是来解释第一句话的，相当于一个主旨句和一个解释句。
When引导的从句就是恐龙灭绝时哺乳动物兴起这样一个并列结构。
所以答案选项总体上是一个由具体到概括的结构，而具体的例子是个并列的结构。
B选项，一个because一个when, 很好地吻合了原文的and when。
答案即选B。
2.key words—推断（inference）针对题型：定位题解题步骤：1.找题干句关键词（指代，承接，解释，转折……）;2.找原文关键词(指代，承接，解释，转折…….)3.通过关键词匹配准确定位。
例4TPO34 Islamic Art and the BookPapermaking had been introduced to the Islamic lands from China in the eighth century. 【】It has been said that Chinese papermakers were among the prisoners captured in a battle fought near Samarqand between the Chinese and the Muslims in 751, and the technique of papermaking – in which cellulose pulp extracted from any of several plants is first suspended in water, caught on a fine screen, and then dried into flexible sheets – slowly spread westward. 【】Within fifty years, the government in Baghdad was using paper for documents. 【】Writing in ink on paper, unlike parchment, could not easily be erased, and therefore paper had the advantage that it was difficult to alter what was written on it. 【】Papermaking spread quickly to Egypt –and eventually to Sicily and Spain –but it was several centuries before paper supplanted parchment for copies of the Koran, probably because of the conservative nature of religious art and its practitioners. In western Islamic lands, parchment continued to be used for manuscripts of the Koran throughout this period.Look at the four squares 【】that indicate where the following sentence could be added to the passage.This change occurred for good reason.Where does the sentence best fit?[解析]关键词:This change, reason。