自从老托福转变成新托福以来，听力考试就一直是考生的一个挥之不去的梦魇，个位数听力分数的惨案时有发生。究其原因，有些考生直接了当告诉笔者，他连讲什么内容都没有听懂，只知道和某个话题有关。这在听力中是致命的，因为就算是听力的主旨题问得也不仅仅是话题，而是大话题之下的一个分类。打个比方，一个学生在听力中重复听到memory, infant 这两个词，感觉这篇文章是讲婴儿记忆力的，但是主旨题让你选three explanations for infantile amnesia。这就无形中增加了难度。俗话说，擒贼先擒王。听一篇学术讲座的听力如果连讲座主旨也没搞懂，再继续往下听也是徒劳。
为了让新托福考生能从容应对听力考试，我们首先来看一下，怎样把学术讲座的听力来听懂？
通俗点来说，每一个
托福听力都是一个有开头有结尾的讲座，只不过学术听力长度6-7分钟，是正式讲座的微缩版。麻雀虽小，五脏俱全。95%的讲座人都会在开头将他今天要讲的主旨给抛出来，也就是说，当考生能抓住讲座人抛主旨的句子，主旨题也就胜券在握了。一般来说，托福学术听力的开头的形式是多种多样的。教授利用各种形式开头，无非就是为了引起学生的注意，因而可谓是用尽了各种手段和套路。但是不变的就是每个讲座人都会把主旨放在这样一个句型结构中：Today, I’d like to talk about~~~/ Let’s begin our class by talking~~/ So today I want to talk about~~/ 以及将主旨句的语速放缓，语调上加重语气。
但是考生会问，我究竟要等多久才能听到主旨句呢？经过归纳与总结，笔者将开头按重要性分为以下三种：
1.直奔主题型:这类开头三句话之内一定有题的答案。这一类教授通常都属于研究类人员，没有过多的说辞。而70%以上的新托福学术听力都属于这一类开头。而直奔主题型的开头又内部分为
先回顾上一次课堂内容，然后牵引出今天的主题
Example:
What is the discussion mainly about?
○Catherine de Medici’s entertainments
○The figures for court dancing
●The development of ballet
○The relationship between dance and meals
原文开头Sorry about the tests. I don't have them finished. They just took longer to grade than I thought they would. So . . . I'll have them for you next time. Okay then. Let's begin our discussion of the ballet. . . .
直接将今天的主旨引出
Example：
What does this lecturer mainly discuss?
●Transcendentalism
○Puritanism
○Ralph Waldo Emerson
○Nature
原文开头：Professor: Today we'll discuss Transcendentalism. Transcendentalism . . .which is a philosophical and literary movement that developed in New England
in the early nineteenth century.
2.信息充斥型:这类开头学生易受到严重打击，教授喜欢堆砌大量相关却与主题不符的信息在开头，等学生听到晕时再抛出主题，旨在显示自己的学术地位，多为科普类文章居多，这类开头术语颇多，就算压不到你也恶心死你。这类开头一般颇长，可能有1-2分钟的废话，考生一旦听不懂就有些想放弃。但是考生一定要秉承“不抛弃，不放弃”的精神，坚持到听到主旨句。
Example：
What is the lecture mainly about?
○The process of photosynthesis
●The major types of oil traps
○A method for collecting gas
○A comparison of gas and oil
原文开头：Professor: The original source of energy is what? The Sun. Then plants use the Sun's energy during photosynthesis to convert water and carbon dioxide into sugar and oxygen, and they store the energy in the chemicals that the plant produces. When animals eat plants, the energy is transferred to their bodies. So then, the plants and animals die and decay, and they sink to the bottom of the sea or . . . or disintegrate into the soil and then they're covered by more and more sediment as rivers deposit mud and sand into the sea or the seas advance and retreat. Of course, it's a very gradual process . . . one that takes place over, well, millions of years. But finally, the organic material begins to transform into the hydrocarbons, and the hydrocarbons eventually become oil and gas deposits. So how does this happen? Well, at first, the oil and gas are mixed with sand and sediment but . . . as the layers on top increase, then so does the pressure. And under pressure, mixtures of oil and sand and water . . . they seep down through the layers of porous rock . . . that's usually sandstone or limestone . . . so they sink down until they reach a layer of nonporous rock, and that's where they pool because they can't pass through the nonporous rock.
Okay. Sometimes there are breaks in the layers of rocks and the breaks allow oil and gas to bubble up and . . . and eventually they reach the surface of the Earth again. So, when this happens, the gas and some oil evaporate into the air . . . but they leave a sticky black tar that appears in pools or pits on the surface. But most crude oil is found in underground formations, which we call traps.
So today, I want to talk about the major types of oil traps.In all the different types of traps, the oil collects in porous rocks, along with gas and water. And, over time, the oil moves up toward the surface of the Earth through cracks and holes in the porous rock . . . until it reaches a nonporous rock deposit . . . and the nonporous rock, remember, it won't allow the oil to continue moving. So the oil becomes trapped under the nonporous rock deposit.
3.花哨型:这种类型的开头噱头实足，之前会举出和主题无关的大量信息，然后再引导学生进入主题。比如举例，提问等等。但是这些都不重要，因为在主旨题没有出现之前，其他题目是不会出现的，托福的出题顺序是按照讲座听力往下走的。
Example：
What is the discussion mainly about?
○The history of the English language
●Different types of grammar
○A linguistic perspective for Latin
○Standard language in schools
原文开头：Professor: What comes to mind when I say the word grammar?
Student 1: That's easy. English class and lots of rules.
Student 2: Memorizing parts of speech . . . like nouns and verbs.
Student 3: Diagramming sentences.
Professor: Well, yes, that's fairly typical. But today we're going to look at grammar from the point of view of the linguist, and to do that, we really have to consider three distinct grammars for every language.
