2010年3月中级力Talk部分第四篇解析

这是一篇科技背景的talk, 话题关于gravitational attraction 即“重力吸引”。 虽然是科技背景，但考生们完全可以用常识猜出一些科学现象的理由。而且文章非常规范，通过一些列连接词指引，所以我们能够排除大量junk information而直接解题。 

We are so used to our life on the surface of the earth that it is not easy for our minds to break free of all the ideas that we take for granted. For example, we can feel things are heavy, so we think of weight as being a fixed quality in an object. But actually, it is not fixed at all. If you could take a one-pound packet of butter four thousand miles out from the earth, it would weigh only a quarter of a pound. The reason for such a change of weight is this: all objects have a natural attraction for all other objects. This is called gravitational attraction, but this power of attraction between two objects gets weaker as they get farther apart. So the weight of an object on the surface of the earth is not the same as its weight 4000 miles out in space. What about the weight of a one-pound of butter on the surface of the moon? There won’t be attraction between the butter and the moon, but the butter will weigh only about 1/6 as much as it does on the earth. This is because the moon is so much smaller than the earth. The amount of a gravitational pull that a body produces depends on the amount of material in it. A packet of butter has a gravitational pull of its own, but it is very small in relation to the pull of something as large as the moon or the earth.  

Q23: According to the speaker, what quality of an object is taken for granted by people?
文章开篇即引入说很多事情被我们想当然了，take for granted这个词汇即时没听懂，也可以记下一笔。接下来for example就引出了考点，例举说明前面的问题。然后我们听到了fixed一词，迅速可以做出选择。

Q24: How much will a pound of butter weigh if it is brought 4000 miles into space?
中段出现了问句what about …，一般这都是考点的出现。只要集中一般都能轻松拿下，听到1/6。即可选择。

Q25: What is the gravitational attraction?
讲话中我们一定要锁定两个关键点，一是new information, 二就是文章的链接词。在新信息gravitational attraction出现后我们要特别小心，然后连续出现两个重要的链接词, but和so。 一般so之后都是对这一话题的总结，即考点。所以要特别关注。 这样我们迅速找到了重力引力的特点，即离得越远，引力越小

Q26: Why does an object weigh much less on the moon than it does on the earth?  
最后部分出现的because, 对应了问题的why. 即可找到相关点，即引力大小不仅和物体本身有关，也和相对应物体的引力有关。这类表原因的词我们曾经专门总结过, 比如：conclusion; due to; attributable; thanks to等等