托福阅读中的句子插入题，即Official Guide列出的第八种题型(Type 8: Insert Text)，在托福阅读考试中一般每篇文章都会出现一题。让我们先来看一道例题：

Modern attitudes to Roman civilization range from the infinitely impressed to the thorough disgusted. As always, there are the power worshippers, especially among historians, who are predisposed to admire whatever is strong, who feel more attracted to the might of Rome than to the subtlety of Greece. At the same time, there is a solid body of opinion that dislikes Rome. For many, Rome is at best the imitator and the continuator of Greece on a larger scale. Greek civilization had quality; Rome, mere quantity. Greece was the inventor; Rome, the research and development division.

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

They esteem symbols of Roman power, such as the massive Colosseum.

Where would the sentence best fit? Click on a square to add the sentence to the passage.

怎样解答句子插入题呢？如果只是把原文整段话从头到尾读上一遍，同时把加黑这句话代入四个黑框逐个验证，这样来确定答案显然是非常耗时的，而且对考生的阅读功力要求很高。其实，我们可以从两个最基本的问题入手，来寻找更简便的解题思路。

很显然，原文这段话在正确的位置插入加黑的这句话之后，应当是语义通顺、上下连贯的。那么第一个问题就是：怎样让一段话上下连贯？这就涉及到了句与句之间的衔接手段。大致有三种手段。最容易想到的就是在两句之间使用逻辑关系词。句与句之间存在一定的逻辑关系，通过逻辑关系词可以将这种逻辑关系清晰地表现出来，句与句之间的衔接就变得非常自然。第二种手段就是后一句使用代词和定冠词the来指代前一句的内容。比如这样两句话：A Chinese writer is giving a speech. He is Mo Yan.这两句话之所以衔接自然，就在于后一句的He指代了上一句的A Chinese writer。第三种手段就是话题的相关性。前后两句话只要是围绕近似的话题，那么它们之间即使没有明显的逻辑关系词，没有指代关系，也可以衔接地非常自然。请体会这样两句话：I love reading. My uncle often invites me to his private library.只是“阅读”这样一个共同的话题就可以把两个看似松散的句子很自然地连接起来。

句子衔接的这三种手段实际上就是我们解题的“线索”。假设有这样一个加黑的句子需要插入原文：Miss Tian also studied at this famous school.我们可以分析得到三大线索：

逻辑关系词：also
显然，这句话的前一句有一个类似的表述。
指代：this famous school
显然，这句话的前面肯定提到了某所著名学校。
话题：studied
显然，这句话的前后两句很可能也在描述关于学习的事情。

综合这三大线索，我们非常容易推测到，这句话前面一句极有可能是在说某人在某所学校学习。于是我们可以到原文中寻找符合我们推测的一句话，加黑的句子只要放在它的后面就对了。最终我们在原文中找到了这样一句话：Mr Wang once was an EMBA student of Cheung Kong Graduate School of Business. 再插入我们这句加黑的句子，连起来翻译就是：王先生曾经是长江商学院的EMBA学员。田小姐也曾在这所著名学校学习。

这简直是Perfect match,你懂的！

现在回头来解答我们的例题。我们先看插入句，可以找到指代和话题两大线索，推测出上面一句很可能在说一群人崇拜罗马。我们看到原文第一句主语是Modern attitudes和一群人无关，所以A选项可以排除。原文第二句完全符合我们的推测，说的是一些罗马权利的崇拜者，所以B选项正确。
让我们再来看几道TPO的题目，应用我们的解题思路。

Third, is it possible to interpret accurately the subject matter of ancient rock art, bring to bear all available archaeological techniques and the knowledge of present-day Aboriginal informants?

The age of Australia’s rock art is constantly being revised, and earlier datings have been proposed as the result of new discoveries. Currently, reliable　scientific evidence dates the earliest creation of art on rock surfaces in　Australia to somewhere between 30,000 and 50,000 years ago. This in itself is an almost incomprehensible span of generations, and one that makes　Australia’s rock art the oldest continuous art tradition in the world.

While a great deal of information exists, the answers to these questions are not yet definitive.

插入句中的these questions说明前面一句很可能提出了一些问题，有问题就很可能有问号，而第一个黑框前恰好有一个问号，所以答案选A。

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 in front of the right wall or the left wall, they showed no signs of confusion.

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

插入句中的He说明前面一句很可能在说某个男人，我们扫一遍原文各句的主语，只有第一句Kramer可能是个男人，所以只能选A。
Observational assessment techniques have become much more sophisticated,　reducing the limitations just presented. Film analysis of the infant's responses,　heart and respiration rate monitors, and sucking devices are used as effective tools in understanding infant perception. Film analysis permits researchers to carefully study the infant's responses over and over and in slow motion.　Precise measurements can be made of the length and frequency of the infant's attention between two stimuli. Heart and respiration monitors provide the investigator with the number of heartbeats or breaths taken when a new stimulus is presented. Numerical increases are used as quantifiable indicators of heightened interest in the new stimulus.

The repetition allows researchers to observe the infant's behavior until they reach agreement about the presence and the degree of the infant's response.

插入句中的定冠词the加上repetition，说明上面一句很可能提到了某种重复，而我们在原文第二个黑框前面找到了over and over（一遍又一遍），所以B是正确选项。

The diffusion of agriculture and later of iron was accompanied by a great movement of people who may have carried these innovations. These people probably originated in eastern Nigeria.Their migration may have been set in motion by an increase in population caused by a movement of peoples fleeing the desiccation, or drying up, of the Sahara. They spoke a language, prior-Bantu (“Bantu” means “the people”), which is the parent tongue of a language of a large number of Bantu languages still spoken throughout sub-Sahara Africa. Why and how these people spread out into central and southern Africa remains a mystery, but archaeologists believe that their iron weapons allowed them to conquer their hunting-gathering opponents, who still used stone implements. Still, the process is uncertain, and peaceful migration—or simply rapid demographic growth—may have also caused the Bantu explosion.

These people had a significant linguistic impact on the continent as well.

插入句中的These people说明上一句很可能提到了一群人，可惜原文这段话一直在说一群人的事情，所以据此无法确定答案。我们又注意到插入句的话题是linguistic impact，讲的是跟语言有关的东西，所以它的前后两句很可能也在谈语言。我们在原文第二个黑框后面找到了They spoke a language，而它和后一个黑框之间还隔了一个跟语言无关的句子，所以插入句只能放在第二个黑框，选B。

下面我们需要考虑第二个问题：插入句的性质。

句子插入题直到倒数第二题才出现。而此句要插入的段落却可能是文章开头几段。ETS要确保这种设计的人性化，就必须保证：即使不插入这句话也并不影响文章的理解和前面十几道题的作答。

从本质上说，插入句是可有可无的！我们再看一遍开始的例题就会发现，原文的整段话已经非常通顺、完整，而那个插入句不过是一个可有可无的补充罢了。

既然如此，我们只要发现原文任一黑框的前后两句话衔接紧密，就可以直接排除此选项了，完全可以不看插入句。至于如何判断原文某处衔接是否紧密，说到底还是要观察上面所说的三大衔接手段：逻辑关系词、指代、话题。

为了便于理解，笔者在此不得不“三俗”一把。句子插入题其实就好比“第三者插足”。原文各个句子之间本来像夫妻一般完整和谐；我们要插入的句子就是一个“小三”，是可有可无的。如果我们发现某对夫妻亲密无间，那么这时候不管“小三”长成什么样都是肯定插不进去的，我们看都不用看她。但不可否认，大多数夫妻的关系不是牢不可破的，“小三”是有可乘之机的，至于最后能否成功“插足”，我们需要寻找线索，综合分析。
基于我们对句子衔接手段和对插入句性质的认识，我们最终可以得到一个快速解题的步骤：

1. 看插入句，在句子里头找线索（逻辑关系词、指代、话题），据此推断上一句的内容。

2. 读原文，每句话只须读主干，找到线索（逻辑关系词、指代、话题）即可，排除衔接紧密的句子，寻找与推断相符的句子。