句子插入题(Insert Text Questions)是托福阅读考试必考题型，出现在每一篇文章倒数第二题，大部分考生在做此题时遇到模棱两可的答案情况较多，容易选错。朗阁的专家将针对这个问题，具体分析句子插入题的考试特点及解题技巧。

　　一、题型特点

　　句子插入题顾名思义就是给一句新的句子，要求考生们把这个句子插入到相应的位置，指定位置是文章中四个黑色方块的地方。这些方块分布在句首或句末，四个方框有时都出现在一个段落里，有时分布在一段的末尾和下一段的开头。考题形式如下：

　　Look at the four squares[■]that indicate where the following sentence could be added to the passage.

　　[…………………]

　　Where would the sentence best fit?

　　同学们要做的是点击其中的一个方块并将这个句子插入文章。

　　句子插入题考查的内容是句子与句子间的逻辑关系，即所插入句子必须和前后句子在逻辑关系上保持一致。其实和我们写作一样，同学们不能把两句毫无关系的句子放在一起。那么在英语里为了体现句与句之间的逻辑关系，会采用各种衔接手段将句子连接起来，所以我们只要熟悉各种句子衔接手段，我们就能立即判断出来句子所插入的相应位置。以下，我们将对考试中经常出现的几种衔接手段进行详细分析。

　　二、解题方法

　　1.词重复适用

　　这种衔接方法简单粗暴明了，无需花费大量脑细胞，完全是送分题。后面一个句子里重复使用前面句子提到的同一个词（通常是名词），使用此方法，我们可以清楚知道作者仍然在谈论同一主题，因为前后句子在意义上关系密切，互相连贯。

　　Their competition and collaboration were creating the broadcasting industryin the United States,beginning with the introduction of commercial radio programming in the early 1920s.■With financial assets considerably greater than those in the motion picture industry,and perhaps a wider vision of the relationships among entertainment and communications media,they revitalized research into recording sound for motion pictures.■In 1929 the United States motion picture industry released more than 300 sound films—a rough figure,since a number were silent films with music tracks,or films prepared in dual versions,to take account of the many cinemas not yet wired for sound.■At the production level,in the United States the conversion was virtually complete by 1930.■In Europe it took a little longer,mainly because there were more small producers for whom the costs of sound were prohibitive…

　　Look at the four squares[■]that indicate where the following sentence could be added to the passage.

　　When this research resulted in the development of vastly improved sound techniques,film studios became convinced of the importance of converting to sound.

　　前面一句话已经提及到了research,第二次出现用this research,所以答案选第二个选项。

　　So,in another set of experiments,Kramer put identical food boxes around the cage,with food in only one of the boxes.■The boxes were stationary,and the one containing food was always at the same point of the compass.■However,its position with respect to the surroundings could be changed by revolving either the inner cage containing the birds or the outer walls,which served as the background.■As long as the birds could see the Sun,no matter how their surroundings were altered,they went directly to the correct food box.■Whether the box appeared…

　　Look at the four squares[■]that indicate where the following sentence could be added to the passage.

　　He arranged the feed boxes at various positions on a compass.

　　不定冠词a compass在*句话里再次出现用的是特指the compass,所以答案选*个黑框。

　　2.词指代替换

　　带有代词题型也比较简单明了，为了避免重复，我们通常会在第二个句子使用代词代替前面（或者后面）提到过的事物（一个词）或者事件（一句话）。所以同学们只要正确找到代词所指就能做对此题。形式一般是this+名词，或者this单独用于指代前面一句话。

　　Since 1980,the use of wind to produce electricity has been growing rapidly.█In 1994 there were nearly 20,000 wind turbines worldwide,most grouped in clusters called wind farms that collectively produced 3,000 megawatts of electricity.█Most were in Denmark(which got 3 percent of its electricity from wind turbines)and California(where 17,000 machines produced 1 percent of the state’s electricity,enough to meet the residential needs of a city as large as San Francisco).█In principle,all the power needs of the United States could be provided by exploiting the wind potential of just three states—North Dakota,South Dakota,and Texas.█

　　Look at the four squares[■]that indicate where the following sentence could be added to the passage.

　　Some companies in the power industry are aware of this wider possibility and are planning sizable wind-farm projects in states other than California.

　　代词this wider possibility这种更加广泛的可能性指代上一句话中的情态动词could be,情态动词could be在这里表示可能性，所以答案选*后一个选项。

　　Under very cold conditions,rocks can be shattered by ice and frost.Glaciers may form in permanently cold areas,and these slowly moving masses of ice cut out valleys,carrying with them huge quantities of eroded rock debris.█In dry areas the wind is the principal agent of erosion.█It carries fine particles of sand,which bombard exposed rock surfaces,thereby wearing them into yet more sand.█Even living things contribute to the formation of landscapes.█Tree roots force their way into cracks in rocks and,in so doing,speed their splitting.In contrast,the roots of grasses and other small plants may help to hold loose soil fragments together,thereby helping to prevent erosion by the wind.

　　Look at the four squares[■]that indicate where the following sentence could be added to the passage.

　　Under different climatic conditions,another type of destructive force contributes to erosion.

　　another是不定代词，指代后一句提到的另外一种destructive force。*整个段落分析，*句话destructive force包括ice和frost,第二句话另外一种destructive force指代的是wind,所以选*个黑框。

　　阅读中常出现的代词：this,this+n,these,another,such and other etc.

　　3.词同义替换

　　此类句子衔接的方法是指所插入句子里面的词（通常是名词）与所在位置前后句子的词同义替换，这种方法要求会比较高，考生除了要理解插入句子里面词的意思，还要找到所在段落里面与它同义的词。

　　█Watt's steam engine soon showed what it could do.█It liberated industry from dependence on running water.█The engine eliminated water in the mines by driving efficient pumps,which made possible deeper and deeper mining.█The ready availability of coal inspired William Murdoch during the 1790s to develop the first new form of nighttime illumination to be discovered in a millennium and a half.

　　Look at the four squares[█]that indicate where the following sentence could be added to the passage.

　　The factories did not have to go to the streams when power could come to the factories.

　　这个句子里面的factories与前一句里的industry同义替换，这里同义替换并不是指两个词要完全对等才能同义替换。只要两个词之间在某一部分是表同义的就可以。比如说工业必然会涉及到很多工厂建立，所以我们可以说两个词是同义替换。答案选第三个黑框。

　　Not only could Smith identify rock strata by the fossils they contained,he could also see a pattern emerging:Certain fossils always appear in more ancient sediments,while others begin to be seen as the strata become more recent.█By following the fossils．Smith was able to put all the strata of England's earth i