3)信息的重复
还有一些插入句，既不包含指代词，也不包含逻辑词。但这类插入句的难度其实并不大。
和所有插入句相同，不包含信息词的插入句也和正确位置的前句或后句存在语义上的联系，这个联系就是信息的重复。当我们找到原文某一个句子，所述内容与插入句内容相关时，再来判断应该把插入句放在这个句子的前面还是后面，就能得到答案了。
看一道例题会更清楚。
Paragraph 3: It used to be believed that before 3000 B.C.E. the political and economic life of the cities was centered on their temples, but it now seems probable that the cities had secular rulers from earliest times. █Within the city lived administrators, craftspeople, and merchants. (Trading was important, as so many raw materials, the semiprecious stones for the decoration of the temples, timbers for roofs, and all metals, had to be imported.) █An increasingly sophisticated system of administration led in about 3300 B.C.E. to the appearance of writing. █The earliest script was based on logograms, with a symbol being used to express a whole word. █The logograms were incised on damp clay tablets with a stylus with a wedge shape at its end. (The Romans called the shape cuneus and this gives the script its name of cuneiform.) Two thousand logograms have been recorded from these early centuries of writing. A more economical approach was to use a sign to express not a whole word but a single syllable. (To take an example: the Sumerian word for " head” was “sag.” Whenever a word including a syllable in which the sound “sag” was to be written, the sign for “sag" could be used to express that syllable with the remaining syllables of the word expressed by other signs.) By 2300 B.C.E. the number of signs required had been reduced to 600, and the range of words that could be expressed had widened. Texts dealing with economic matters predominated, as they always had done; but at this point works of theology, literature, history, and law also appeared.
City life was diverse, and the population was engaged in a variety of occupations.
插入句并没有指代词和逻辑词出现，只表达了句意“城市里有着多种多样的生活和工作”。这个时候，我们直接回原文，寻找哪个句子提到或围绕“城市里的生活和工作”进行论述。发现原文第二句话“Within the city lived administrators, craftspeople, and merchants.”，其实就是具体的阐述city里的工作都有什么，人们都干嘛，与插入句句意是重复的。且前面一句话最后提到了secular，暗指的其实就是日常生活和工作。所以A是最合适的位置。
前一句话先表达出“除了政治经济和宗教活动，cities还有很多日常活动”，紧接着后两句话先总述“城市中的(日常)生活和工作是多种多样的”，之后再非常具体的举例描述都存在什么样的工作和生活，前后逻辑非常吻合，语意流畅。
4)综合
Another flaw of the tiredness theory is that yawning does not raise alertness or physiological activity, as the theory would predict. When researchers measured the heart rate, muscle tension and skin conductance of people before, during and after yawning, they did detect some changes in skin conductance following yawning, indicating a slight increase in physiological activity. However, similar changes occurred when the subjects were asked simply to open their mouths or to breathe deeply. Yawning did nothing special to their state of physiological activity. Experiments have also cast serious doubt on the belief that yawning is triggered by a drop in blood oxygen or a rise in blood carbon dioxide. █Volunteers were told to think about yawning while they breathed either normal air, pure oxygen, or an air mixture with an above-normal level of carbon dioxide. █If the theory was correct, breathing air with extra carbon dioxide should have triggered yawning, while breathing pure oxygen should have suppressed yawning. █In fact, neither condition made any difference to the frequency of yawning, which remained constant at about 24 yawns per hour. █Another experiment demonstrated that physical exercise, which was sufficiently vigorous to double the rate of breathing, had no effect on the frequency of yawning Again the implication is that yawning has little or nothing to do with oxygen.
This, however, was not the case
本句既出现代词“this”也出现逻辑词“however”，不过this指代内容比较模糊。可以推测出，前面提到的句意，在插入句中得到了否定(not the case)。其次，根据however存在的转折和承上启下的关系，后文非常有可能展开论述this指代内容为何不是真实情况(not the case)。结合推测，找到C位置的前后，符合这个关系。前一句话说“如果理论正确，则呼吸二氧化碳多会导致打哈欠增多，呼吸氧气多会减少打哈欠”，后一句话表示“真实情况是(in fact)，不管是二氧化碳还是氧气，打哈欠的频率都是相同的”，所以后一句话就是通过描述真实情况，而对前一句理论所推测和估计的情况起到反驳的作用。
4. 记得带进去检验哈
检验指的是前文做题步骤中的第四步：将句子放入，讲插入句及前后两句话连起来通读一遍，检验是否流畅逻辑严谨、语意流畅。
这个步骤必不可少，来看一道例题。
Paragraph 1: It has long been accepted that the Americas were colonized by a migration of peoples from Asia, slowly traveling across a land bridge called Beringia (now the Bering Strait between northeastern Asia and Alaska) during the last Ice Age. █The first water craft theory about the migration was that around 11,000-12,000 years ago there was an ice-free corridor stretching from eastern Beringia to the areas of North America south of the great northern glaciers. It was the midcontinental corridor between two massive ice sheets-the Laurentide to the west-that enabled the southward migration. █But belief in this ice-free corridor began to crumble when paleoecologist Glen MacDonald demonstrated that some of the most important radiocarbon dates used to support the existence of an ice-free corridor were incorrect. █He persuasively argued that such an ice-free corridor did not exist until much later, when the continental ice began its final retreat. █
Moreover, other evidence suggests that even if an ice-free corridor did exist, it would have lacked the resources needed for human colonization.
本句出现“moreover”，表示插入句和前文是递进关系，表示进一步的论述。后面出现“other evidence”，指出前面应该有某些evidence。句中出现even if的让步关系，再结合句意“此外，其他证据表明，即使无冰走廊确实存在，它也会缺乏人类居住所必须的资源”，可以推测出，前文的evidence应该是在论证“ice-free corridor”不存在，这里才会递进+让步，表示“即使存在，也…”的句意。根据这个推测发现C位置前面一句话指出：Glen Macdonald证明支持“ice-free corridor”存在的信息其实是错误的。也就是在暗示“ice-free corridor”不存在，能够和插入句紧密连接。
但万万没有想到的是，C位置后面依旧在论述这种corridor不存在：他非常有力地指出，这种无冰走廊直到之后的时期才出现。并且此句中开头第一个单词就是“he”，指代的是前句所论述的Glen Macdonald，而插入句却并没有能够满足he这个指代的内容。所以，插入句应该放在D位置，待本段最后两句话把corridor不存在的事情讲完，再出现“moreover”进行递进。
这个题目告诉我们，不仅需要确认某个位置的前文与插入句紧密连接，还要往后看一句，确保万无一失。
以上内容已将插入句子题几乎所有情况都进行了论述，并且介绍了针对的解题思路，各位好好消化和吸收哦!
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