对话结构
对话部分，常见的文章结构模式为，出现一个问题，比如说图书馆里要借书但是找不到，比如说学期论文要找个主题找不到，比如说要去报告一下宿舍的空调需要维修等，那么接下来肯定会提出解决问题的方案，但是前提是对话的时长通常为3分钟左右，所以老师或者教职员工肯定不会很直接地就把这个问题给解决了，试想，图书管理员把书找给了学生，那么这个对话接下来的故事情节只能是Thank you, bye了。
所以，总结起来，对话的文章结构一般分成四个步骤：
1. problem, 即学生出现一个问题;
2. solutions, 老师提出一些问题的解决方案，通常这部分的内容会出现好几个解决方案;
3. result, 问题的处理结果;
4. development, 跟话题本身相关的内容扩展延伸。
比如说TPO16 Conversation1 Listen to a conversation between a student and a facilities manager at the university.
文章内容主要讲的是因为有工地建设的原因，排练教室特别吵(problem), 老师说要不换个时间(solution), 学生说不行，好像组员们都有安排了。老师又建议说换成music building(solution), 最后终于解决了问题，换了一个带有礼堂的地方进行排练。
再比如TPO9 Conversation1 Listen to a conversation between a student and her professor.
文章主要内容讲的是学生想问一下关于论文的主题(problem), 学生准备写牛奶包装对于牛奶价值营养等的影响，老师给出了建议(solution), 最后，老师提到了在切尔西有个奶牛场，能对于学生写论文有帮助(development)。
以上，常见的对话文章结构了解清楚了，也就是对于文章的考点段落进行了分段归纳，比如在步骤一(problem)部分，考生可以专心听问题本身是什么内容，听力考题部分第一题主旨目的题就可以找出答案了。常见的problem的表述分为三类：一是学生直接说I want to… I was wondering…; 二是学生委婉地说I have trouble/hard time/difficulty to do something; 三是老师会问Can I help you?之类。
讲座部分的文章结构稍微多一些。大体分成如下几类：平级并列类、举例类、顺序类、对比类以及过程类这五种。
讲座结构：平级并列类
顾名思义，这种结构通常是很明显的，也是相对来说最简单的一种，不管考生听力能力好坏，或多或少都是能把握的。比如TPO41Lecture1, 这是一篇botany的讲座文章，主题是在讲Different ways that plants have adapted to desert environments. 主旨以外全篇文章分成了三段话，分别讲了三种植物——succulent plant、drought-tolerant plant、annual plant这三段话。原文是这样说的：Many different species have developed each of the adaptations. So, first off, there are succulent plants…now, besides succulent plants, there’re also drought-tolerant plants…the third adaptive strategy is to avoid the drought conditions altogether. Yes! There are plants that do this: annual plants!
2. What are two features of succulent plants that help them survive in deserts?
3. Why does the professor mention bears?
4. What is one ability that drought-tolerant plants have that succulent plants do not have?
5. Why can annual plants grow in a desert even after a year of no rainfall?
以上是这篇文章所对应的题目，从出题的角度来讲，这篇平级并列就是考到了文章中讲到的三种植物succulent plant、drought-tolerant plant、annual plant，每个段落考一种。值得注意的是，平级并列结构可能会出现一些比较的考点，在备考过程中值得考生们去注意，比如其中的第四题就是如此。
讲座结构：举例类
举例是常见且常被用的一种文章构思方法。就举例类文章而言，托福听力中类似文章结构的听力文本实在是非常的多，甚至在结构题中还出现过考题。比如在TPO26Lecture1 advertising class中，文章交代好背景以后，就开始例子的讲解了。The seeds for green marketing were probably planted in 1970, when the first Earth Day took place. Rallies all over the United States were organized to protest environmental degradation. Some 20 million demonstrators participated in that first Earth Day. And it helped spark dozens of environmental laws… A few years later, we began seeing ads tapping into people’s environmental concerns. But some green marketers learned the hard way, green marketing must still involve all the same principles of a traditional marketing campaign. You ad must attract attention, stimulate consumers’ interest, create a desire for your product, and motivate people to take action to buy your product. So let me tell you about one green marketing campaign that failed at first and explain why. It was a compact fluorescent light bulb.
而后整篇文章都在讲关于这个bulb的营销是如何失败的，而且也考到了结构题。
7. How does the professor organize the lecture?
A. She gives some historical background, then she presents a case study.
B. She describes several environmental friendly products, and then she explains how the public responded to them.
C. She describes a problem, and then she proposes several possible solutions.
D. She describes an approach to advertising, and then she explains why it is often ineffective.
这道题目就是举例结构文章的典型，答案应该是A选项，在交代了historical background以后就开始说case study了。
这种举例类的文章还有一个需要注意的点。通常举例类的文章结构下，例子本身的内容叙述篇幅是很长的，部分情况下可能对于主旨题的概括有一定的影响，因为很多考生在备考过程中好像听到的内容时长覆盖比较长。比如TPO42Lecture1 art history的文章中就是如此，文章前半部分讲的是sculpture的各种内容，后半部分在讲一个例子，Augustus这个雕像塑像的实例。而在主旨题的考察中A选项To explain why a particular statue of a Roman emperor is so famous.这个选项中的Roman emperor就是Augustus这个例子本身，所以不可能作为主旨题的答案。
讲座结构：顺序类
顺序类文章结构是比较多的，按照文章的时间顺序或者发展顺序在讲文章的内容，一般文章内容不会带有重复现象，是比较清晰的那种一段一段的内容。
比如TPO26 Lecture2, 文章先讲主题The role trace metals play in carbon cycling,然后再讲了respiration呼吸作用以及photosynthesis光合作用，接着讲的是diatom藻类，再讲cadmium镉。算是环环相扣，一段接一段。
讲座结构：对比类
对比类文章结构在托福听力所有的文章类型中是比较少的。最典型的是TPO5Lecture4,主旨是Differences between fairy tale and folktale。全文就讲了三个点：1. folk tale是什么;2. fairy tale是什么;3. folk tale和fairy tale的共同点和不同点。这种文章结构也是很好理解的，但是这种文章结构的细节点会比较多。
Now, a number of things happen when an oral tale gets written down. First, the language changes. It becomes more formal, more standard - some might say, "Less colorful". It's like the difference in your language depending on whether you are talking to someone, or writing them a letter. Second, when an orally transmitted story is written down, an authoritative version with a recognized author is created. The communal aspect gets lost. The tale no longer belongs to the community. It belongs to the world, so to speak. Because of this, elements like place and time can no longer be tailored to suit a particular audience. So they become less identifiable, more generalizable to any audience. On the other hand, descriptions of characters and settings can be developed more completely. In folk tales, characters might be identified by a name, but you wouldn't know anything more about them. But in fairy tales, people no longer have to remember plots. They're written down, right? So more energy can be put into other elements of the story like character and setting. So you get more details about the characters, about where the action takes place, what people's houses were like, ur, whether they're small cabins or grand palaces. And it's worth investing that energy because the story, now in book form, isn't in danger of being lost. Those details won't be forgotten. If a folk tale isn't repeated by each generation, it may be lost for all time. But with a fairy tale, it's always there in a book, waiting to be discovered, again and again. Another interesting difference involves the change in audience. Who the stories are meant for? Contrary to what many people believe today, folk tales were originally intended for adults, not for children. So why is it that fairy tales seem targeted toward children nowadays?
在这一段话中，关于比较的考点一共出现了四处，若是考生习惯了一段话听一个考点的话，那么就会在听力过程中出现遗漏的情况了。
讲座结构：过程类
过程类文章结构是几种文章结构中最难的了，通常可能出现在地质学geology、environmental science或者art history中，这种文章多体现为，在文章内容表述过程中会出现某些内容的重复，使得考生在听力过程中觉得一直在讲某样东西，但是好像又不是很理解。
比如在TPO9Lecture2 environmental science文章中讲到了一个词permafrost, 而这个词在很多段落中都出现了。The tundra has two layers: top layer, which is called the active layer, is frozen in the winter and spring, but thaws in the summer. Beneath this active layer is the second layer called "permafrost", which is frozen all year around, and is impermeable to water.(0: 49-0:55) and their roots don't grow very deep, so the permafrost doesn't interfere with their growth. (1:13-1:18)they live in the active layer, which, remember, contains water that doesn't penetrate the permafrost.(2:39-2:45)
选项中也是，第一题B. How temperature increases might be affecting the permafrost in Arctic Alaska.第二题A. They have roots that can penetrate permafrost. 第三题C. Increases in average winter temperatures have permafrost permeable to water. 第四题C. Most nutrients remain frozen in the permafrost when spring runoff is at its peak. 这四道题目的选项都有permafrost这个词，所以考生听得时候就会抓不住重点，但是又非常明确知道自己的确听到过，选项又极具迷惑性。
对话和讲座结构的混用
TPO26 Conversation1就是这样一个典型的例子，在这篇对话中，学生需要打印一些宣传资料(problem), 老师提出了解决方法(solution), 而在文章中，solution部分老师分别提到了business card, flyer, poster, sticky note, pencil等，其中sticky note和pencil分别作为这篇文章的题目被考到，其实中间这段solutions就是讲座部分平级并列结构的缩小版，肯定会考到平级并列结构其中的一个小段落。按照篇幅的占比，也可以预测出其中的考点。
总结一下，理清文章结构内容，可以从整体行文脉络篇章内容和上下文联系这两个方面，更加有效地帮助考生在备考过程中预测考点所在的段落顺序内容，特别是对于文章结构题部分，对于选项顺序性内容的选项排除法解题效果尤为显著，希望备考考生们能因此受益。
以上就是小编整理的精彩内容希望可以帮助托福考生，更多精彩内容尽在，预祝托福考生取得理想成绩!