托福听力lecture的结构1. Lecture有结构托福听力的lecture基本上都是总分总的结构，即「引入话题——展开讨论——教授总结」，下面分点论述：1）引入话题其实托福听力lecture里面讲课的教授就跟大家碰到过的老师一样，有的喜欢直入主题，有的喜欢拉七杂八。
总的说来，lecture话题的引入方式有三种：•开门见山：啥也不扯，一言不合就开车，比如TPO1 Lecture2：Ok, let’s get started. Great. Today I want to talk abouta way in which we are able to determine how old a pieceof land, or some other geologic feature is –datingtechniques.•课程回顾：回顾上堂课的内容，然后再切入本堂课的内容；一般来说本次是上次的细化或者与上次的对比。
比如TPO5Lecture2：Last week, we covered some arguments against going back to the Moon. But there are compelling reasons in favor of another Moon landing too, um…not the least of which is trying to pinpoint the moon’s age.••啰哩吧嗦：有的教授实在是特别啰嗦，比如TPO2 Lecture2：Hi, everyone. Good to see you all today.【你也好啊】Actually,I expected the population to be a lot lower today. Ittypically runs between 50 and 60 percent on the day theresearch paper is due.【来的人多不好么，说明你受欢迎啊】Um, I was hoping to have your exams back today【啊，要放榜啦】, but, uh, the situation was that I went away forthe weekend, and I was supposed to get in yesterday at five, and I expected to fully complete all the exams by midnightor so, which is the time that I usually go to bed, but myflight was delayed, and I ended up not getting in untilone o’clock in the morning【你飞机晚点关我什么事啊】.Anyway, I’ll do my b est to have them finished by the nexttime we meet【开始上课吧，please】. OK. In the last class,we started talking about...【终于开始了…】不论是用哪一种引入方式，话题总是要出来的。
一般都有一个核心的话题词，这个词后面一般有一个定义或者解释。
比如TPO5Lecture3：...But, let’s talk about Spectroscopy a little now just to cover the basics. What is Spectroscopy Well, the simplest definition I can give you is that Spectroscopy is the study of the interaction between matter and light. 这个「topic+definition/explanation」一定要听懂，最好还能在笔记上记下关键词。
（当然，也有话题词不那么明显的，这样的lecture的结构就稍微难以整理一点。
）在这个「topic+definition/explanation」之后，一般有一句话总起下面的展开讨论的内容。
比如TPO33 Lecture1：The great pyramid of Giza in Egypt might be the most famous building in the world. We know exactly when it was built: construction started in 2547 about four thousand five hundred years ago. We know who had it built: that was a Pharaoh Khufu. And we know who oversaw its construction: the Pharaoh's brother. We know so many things about it, but the funny thing is, we still don't know exactly how it was built.This picture will give you an idea of the size of the pyramid and the size of blocks it's made up of. About two million stone blocks were used to build the great pyramid, and they're incredibly massive. The average weight is two and a half tons. The problem that has puzzled scholars for centuries is how were these blocks lifted up the height of this massive structure and then fit into place and without the benefit of modern technology. Of course there have been a lot of theories over the centuries.其实这就是常见的总起句式「several theories」「a few problems」「scientists have proposed several explanations」，下面的展开讨论部分就是具体展开这些theories、problems或explanations。
小结一下：Lecture的第一个部分包括：引入+话题+定义/解释+总起。
2）展开讨论展开讨论当然紧接着上面的总起，结构往往比较清晰。
比如TPO33 Lecture1在总起「Of course there have been a lot of theories over the centuries」之后就逐个展开这些theories。
这些theories都是解释上面的话题，先提出theory1，讲清楚后再讲theory1的问题；因为theory1有问题，自然就转入了theory2，再以此类推讲theory3、theory4——一般也就是三个或四个theory，再多就太长了。
•The oldest recorded one 【theory1】 is by the Greek historian Herodotus...Well, so much for that theory.•The next one【theory2】has to do with the use of a ramp...【theory2的问题】OK, so what now•Well, if you'd ever driven on a mountain road...So why not wrap the ramp around the pyramid【theory3】... Well, if you've got a ramp spiraling up from the base of the pyramid, those corners would be buried by that ramp duringconstruction【theory3的问题】.•Well, who says the ramp has to be on the outside of the pyramid And now we get to the latest idea【theory4】: if the ramp were on the inside of the pyramid...其实这种就是托福听力lecture的第一种，即「总分总」的多个「分点」之间是并列的关系，比较常见的是「problem+solution1、solution2、solution3」或者「puzzle+explanation1、explanation2、explanation3」。
不论是一个问题+多个解决方案，还是一个疑难+多种解释，不论具体的用词是用solution、explanation还是theory，总体结构都是类似的。
这些结构大多适用于理工科的话题，逻辑比较清晰，转进的逻辑连接词也很明确，占据托福听力lecture的大多数。
另外一种就是「总分总」的多个「分点」之间是直线型的时间关系，多适用于文科的内容。
比如讲到某个作家的生平，一般都是「早年——青年——中年——晚年」，再比如讲到某种乐器的进化史，一般都是「起源——19世纪——20世纪——21世纪」之类的。
比如TPO30 Lecture4：话题引入之后总起But really the instrument [electric guitar] we know today was the result of a continuing development that started for our practical purposes in the 1920s. 然后就分阶段讲述guitar的发展史：•The first guitars were wooden...•the steel guitar was first introduced in the United States...in the late 1890s...•Anyway, by the 1920s...•Electrified guitars... around 1940...很显然，这种直线型结构的关键在于听懂记下这些时间标记。