一篇文章一般表达一个中心或主题。这个中心或主题通常用一个句子来概括，此句叫主题句，这类题主要考查读者把握全文内容或理解中心思想的能力，也包括分析归纳文章段落大意、重要情节、人物特征、写作特点的能力。一般说来说明文和议论文都有主题句，而且多位于文章的开头，有时也位于文章的中间或末尾。但有时不能直接在文章中直接找到主题句，在弄清段与段之间逻辑关系的基础上自己归纳总结。主题句必须能简洁明了地概括全文的主要内容，具有高度的综合性和概括性，文章或段落的其他句子都是对主题句的进一步的解释、说明、论证或拓展。
常见的主旨大意题的考查形式：
The text is mainly about ____.
The main idea／The general idea／The main purpose is ______.
Whats the main point the writer is trying to make in the last paragraph?
What would be the best title /headline for the text?
This article mainly tells about the story of ____.
What is the topic of the text?
The subject discussed in this text is ____.
What does the second paragraph discuss?
The paragraph (passage) deals with _____.
What is mainly discussed in the text?
（二）主旨大意题解题方法与步骤：
略读法是理解全文大意的快速而有效的方法，略读的关键是能抓住文章要点的前提下，以个人最快的速度阅读，主要目的是尽快获得足够的信息以便准确的回答问题，利用略读法去做阅读时，要特别注意首尾两段，要学会寻找文章段落的主题句，这是高效省事地抓住段落要点的捷径，同时也是准确理解文章大意的有效途径。在做题时要注意以下步骤：
1．先看问题，看是否有和主旨相关的题目，了解题目类别和提问方式。
2．再看文章首尾和各段开头，找出主题句或通过浏览全文，抓住关键字眼，把握主旨。
3．以掌握主旨为前提，处理推断作者语气或意图等其他深层次问题。
（三）考题探究
PITTSBURGH ? For most people, snakes seem unpleasant or even threatening. But Howie Choset sees in their delicate movements a way to save lives.
The 37-year-old Carnegie Mellon University professor has spent years developing snake-like robots ，he hopes will eventually slide through fallen buildings in search of victims trapped after natural disasters or other emergencies.
Dan Kara is president of Robotics Trends, a Northboro, Mass.-based company that publishes an online industry magazine and runs robotics trade shows. He said there are other snake-like robots being developed, mainly at universities, but didnt know of one that could climb pipes.
The Carnegie Mellon machines are designed to carry cameras and electronic sensors and can be controlled with a joystick(操纵杆). They move smoothly with the help of small electric motors, or servos, commonly used by hobbyists in model airplanes.
Built from lightweight materials, the robots are about the size of a human arm or smaller. They can sense which way is up, but are only as good as their human operators, Choset added.
Sam Stover, a search term manager with the Federal Emergency Management Agency based in Indiana, said snake-type robots would offer greater mobility than equipment currently available, such as cameras attached to extendable roles.
It just allows us to do something weve not been able to do before, Stover said, We needed them yesterday.
He said sniffer dogs are still the best search tool for rescue workers, but that they can only be used effectively when workers have access to damaged building.
Stover, among the rescue workers who handled the aftermath (后果) of Hurricane Katrina, said snake robots would have helped rescuers search flooded houses in that disaster.
Choset said the robots may not be ready for use for another five to ten years, depending on funding.
What is the text mainly about?
A. Snake-like robots used in industries.
B. Snake-like robots made to aid in rescues.
C. The development of snake-like robots.
D. The working principles of snake-like robots.
学海导航：B 该题是考查文章的主旨大意。文章的第一段只是引出这一话题，第二段才是本文的主题，第二段中提到Choest讲究 snake－like robots是因为he hopes will eventually slide through fallen buildings in search of victims trapped after natural disasters or other emergencies，由此可知，Choset 研究蛇形机器人的目的是为了在自然灾害或其他的紧急事故中起作用。
（四）实例演练
Everyones at it, even my neighbors. I thought I might be the only person left in the world who hadn't done an eBay deal. So, I decided to try my hand at online auction(网上拍卖).
Buying for beginners: Sign up on www. ehay. co. uk. Most items (e.g. tables, computers, and books) ready for auction will come with a picture and a short description; others may be marked with Buy It Now and have a fixed price. You can buy these right away.
If the item is being auctioned, you offer the highest price you are prepared to pay and eBay bids (出价) for you. The bid will be increased little by little until it goes beyond your highest bid, then you are emailed and asked if you would like to bid again. Auctions last up to 10days and when they finish you get an email telling you whether you have won the item.
How to pay: Sellers decide how they would like to be paid and you need to check this before placing a bid as you might not want to post a cheque or postal orders. The easiest way is through PayPal, an online payment system that takes the money away from your credit card (信用).
Selling made simple: If you plan to sell on eBay, it helps to include a picture of the item. I followed my friends' advice and put up the items I wanted to sell for a 10-day auction, starring on a Thursday. This way buyers had two weekends to bid.
The big things in life: It' s easy to post a small item, but furniture is a big part of eBay and this has to be collected or sent by deliverymen. Cheek the ways of delivery before you bid.
What is the passage mainly about?
A. How to make payment online.
B. Ways of making delivery online
C. Advantages of an online-auction system.
D. How to use an online-auction system.
【点津】D本题考察考生对文章主旨要义的理解能力。四个选项均涉及到有关短文内容，但是通过比较其核心概念，会发现A选项为支付首段， B选项为交货方式， C选项为系统优势，D选项为使用方法。由此可见A、B、C三个选项都只涉及了短文部分内容，不具备概括全篇的作用。D选项包含所有内容，能够全面概括出短文的主旨要义。C选项由于说话方式本身具有概括意味，具有一定的干扰。
（五）经验总结:
1．把握逻辑结构，提高这方面的能力对于阅读议论文或说明文尤为重要，在此类文章中常用某个细节来引出题目从而进行议论，在议论的过程中可能会出现一些论据或细节描述，这部分常被设置为此类试题的干扰项。
2．找准主题句，主题句通常在文章句首，句中或句末，主题句表达中心思想，起主导作用，阅读时要对容易出现主题句的地方特别注意。（六）主旨大意题的错误选项有一下特点：
1．以偏盖全。只是局部信息或者是一句没有展开论述的话。
2．过于笼统。即归纳的主题太宽泛，与细节脱节或者是没有对细节加以充分论述。
3． 把观点强加于作者。读者往往根据自己的常识对文章进行判断而忽视了作者的见解。
4．无关信息，即在文章中没有提到或者是找不到语言 依据的信息。
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