关于听力中的main idea
在雅思托福听力考试中对main idea 的把握既是对所听内容的宏观把握，具有十分重要的意义。Main idea既可指听力全文的大意，也可指每个段落的大意。如何在一篇较长的听力文章中准确地把握main idea，除了要靠长时间的积累与练习之外，也要学会一些方法和技巧，用正确的方法来练习可以达到事半功倍的效果。

首先，需了解雅思托福听力考试的基本形式为两类：dialogue 和 monologue.
对于第二、第四步分的monologue（lecture）而言，可以通过以下图示分析对其main idea 的听力技巧：

由此可见，文章中重要观点即main idea 的出现都是遵循同样一种套路，也就是

引述-----观点-----阐释-----总结

那么，signpost 是什么呢？
signpost 就是提醒我们main idea 将出现的标志，signpost 其后紧跟的一句话往往就是观点。
常见的signpost 有两种，一种为虚词，即表明文章框架结构的词如but, so, however, etc. 另一种为实词，即the fact remains that…, this is how to achieve…, as we can see that…, 设问句等.

下面我们以一篇听力练习为例来分析怎样抓住main idea.
              
"Are you happy?" I asked my brother, Ian, one day.
"Yes. No. It depends on what you mean," he said.
"Then tell me," I said, "when was the last time you think you were happy?"
"April 1967," he said.

It served me right for putting a serious question to someone who has joked his way through life. But Ian's answer reminded me that when we think about happiness, we usually think of something extraordinary, a 1)pinnacle of 2)sheer delight. And those pinnacles seem to get rarer the older we get.

For a child, happiness has a magical quality. I remember making hide-outs in newly cut 3)hay, playing 4)cops and robbers in the woods, getting a speaking part in the school play. Of course, kids also experience lows, but their delight at such peaks of pleasure as winning a race or getting a new bike is 5)unreserved.

In the teenage years, the concept of happiness changes. Suddenly it's conditional on such things as excitement, love, popularity and whether that zit will clear up before a 6)prom night. I can still feel the agony of not being invited to a party that almost everyone else was going to. But I also recall the ecstasy of being plucked from obscurity at another event to dance with a 7)John Travolta look-alike.

In 8)adulthood the things that bring 9)profound joy - birth, love, marriage - also bring responsibility and the risk of loss. Love may not last, loved ones die. For adults, happiness is complicated.

My dictionary defines happy as "lucky" or "fortunate", but I think a better definition of happiness is "the capacity for enjoyment". The more we can enjoy what we have, the happier we are. It's easy to overlook the pleasure we get from loving and being loved, the company of friends, the freedom to live where we please, even good health.

I added up my little moments of pleasure yesterday. First there was sheer bliss when I shut the last lunchbox and had the house to myself. Then I spent an 10)uninterrupted morning writing, which I love. When the kids came home, I enjoyed their noise after the quiet of the day.

You never know where happiness will turn up next. When I asked friends what makes them happy, some mentioned 11)seemingly 12)insignificant moments. "I hate shopping," one friend said. "But there's this clerk who always chats and really cheers me up."
Another friend loves the telephone. "Every time it rings, I know someone is thinking about me."We all experience moments like these. Too few of us register them as happiness.

While happiness may be more complex for us, the solution is the same as ever. Happiness isn't about what happens to us; it's about how we perceive what happens to us. It's the 13)knack of finding a positive for every negative, and viewing a 14)set-back as a challenge. It's not wishing for what we don't have, but enjoying what we do possess.

我们注意到，文章中观点出现的地方都有signpost 为提示， 帮助我们找到重点。熟悉文章的框架和脉络就能够轻松地把握文章线索，从而在听力考试中做到掌握主动，驾轻就熟，不慌不乱。进而能够把精力合理分配，抓住重点，以最快的速度找到正确答案。

对于第一、三部分的dialogue 来说，这种方法同样适用，需要注意的是， dialogue 通常采用一问一答的形式，因此应特别注意提问者所问问题。main idea 在多数情况下存在于回答的第一句话，因此要把听时的主要精力放在这句话上。至于其后面的解释和举例多属于干扰信息不一定要求完全听懂。


例如：--And you are doing biology, if I remember it correctly?
      --Yes, although to start with I couldn’t decide between that and geography.
在这里，回答着的肯定答复已经是答案了，至于其后面的多余解释可忽略不计。

Main idea 的听力技巧看似容易，却也需要一段时间的练习才能完全掌握。可以尝试做outline 的练习。即听完一篇文章或对话后自己写出其框架和关键词，帮助自己梳理思路。