閱讀的首要目的是看懂文章的主旨大意，閱讀測試自然也以此作為檢驗學(xué)生閱讀能力的主要標(biāo)準(zhǔn)，辨別文章的中心思想也就成了一種很重要的閱讀技巧，這一技巧同樣在提高閱讀能力和閱讀速度中起著至關(guān)重要的作用。但如何獲取文章的中心思想呢？本文就以段落（構(gòu)成篇章的基本組成單位）為例，來探討一下如何獲取文章的中心思想。

一、如何獲取段落的中心思想

要了解段落的中心思想，可以問自己如下幾個問題：

1．What is the topic？（Whom or what is the paragraph about？）
2．What does the author want me to know about the topic？
3． What general statement expresses what the author wants me to know about the topic？（The main idea is found in the topic sentence．）

［例1］
People have different tastes in food．Some feel that they haven't eaten a meal unless they have had steak or other red meat．Some prefer chicken or fish and eat one or the other at every meal．Others prefer vegetables and fruits or grains and would enjoy a meal of clam chowder， spaghetti，eggplant，and fresh fruit．Others could live on what are called fast foods：a hamburger or hot dog，F(xiàn)rench fries，and a soft drink．

1．The topic is：Tastes in Food．
2．The author wants you to know that peoplehave different tastes in food．
3． The first sentence is the one that expresses what the author wants you to know about the topic．This is the topic sentence expressing the main idea of the paragraph．

不難看出，獲取段落大意的最主要途徑是判斷主題句。主題句常常是一個完整的句子，它簡潔明了，具有概括性，而段落中的其他句子則是對該主題句所表述的主題思想進行解釋、支撐或擴展。
二、主題句在段落中的位置

1．位于段首的主題句
在有主題句的段落中，大多數(shù)情況下主題句是位于段首的，或第一句，或第二句。用演繹法撰寫的段落常遵照這種先概述后分述的寫作程序，它常能給人清晰明了之感，使人馬上就可以明白選文所講的是什么，即文之主題。（見上［例1］）

2．位于收段的主題句

位于收段的主題句也叫結(jié)尾句，這種段落的寫作程序是表述細(xì)節(jié)的句子在前，概述性的句子在后。通常用歸納法撰寫的段落大多如此。

［例2］

In 1959，Brazil lost the World Cup of soccer to Uruguay in Rio de Janeiro．The entire country was overcome by sadness；some people even died from it．Brazilians reacted very strongly to the defeatin the championship soccer game．

Some people had heart attacks，and others beat their heads against cement post．Brazilians are very emotional about soccer．

［分析］

本段描述了巴西人對足球比賽失利的反應(yīng)，如：整個國家沮喪；有人甚至因球賽失利而死；有的人患了心臟病；有的人以頭撞擊水泥柱等。最后的概括是“巴西人對足球的感情是很脆弱的”。

3．位于段中的主題句

出現(xiàn)在段中的主題句有兩種情況，或先提出問題，然后給予回答（主題句），再給予解釋；或先引入主題，然后點出主題思想（主題句），最后給予解釋。

［例3］

Californians and New Englanders are both American．They speak the same language and abide by the same federal laws．But they are very different in their ways of life．Mobility─ both physical and psychological─has made a great impression on the culture of Californians． Lack of mobility is the mark of the customs and morality of New Englanders．

［分析］

本段前兩句講的是加州人和新英格蘭人的共同之處，而第三句卻點出了其不同之處。緊接著短文就其不同之處從mobility（易動性）方面作了比較。顯然，第三句屬主題句。

4．前后呼應(yīng)的主題句

有的段落前后有兩個主題句。兩個主題句述說的是同一內(nèi)容，但用詞不盡一致，這樣不但強調(diào)了主題思想，而且顯得靈活多變。這兩個句子并非簡單的重復(fù)，后一個主題句或者對主題作最后的評述，或者把主題要點作一概括，或使之引申留給讀者去思考。

［例4］
Synonyms，words that have the same basic meaning，do not always have the same emotional meaning．For example，the words“stingy?and“frugal?both mean“careful with money”．However，to call a person stingy is an insult，while the word frugal has much more positive connotation．Similarly，a person wants to be slender but not skinny，and aggressive，but not pushy． Therefore，you should be careful in choosing words because many so-called synonyms are not really synonymous at all．

［分析］

段首的主題句是“同義詞，即基本意義相同的詞，并不總具有相同的情感意義”。段中舉了同義詞stingy和frugal，slender和 skinny， aggressive和pushy的差異。段尾的主題句再次點題，提醒人們在使用同義詞時要特別留心。即“在挑選詞匯時要謹(jǐn)慎，因為許多所謂的同義詞并不 是真正的同義。”
三、隱含（implied）的主題句

有時一個段落沒有主題句，段落是由一個隱含的中心思想凝聚在一起的。對這類段落要采取提綱挈領(lǐng)法，把從細(xì)節(jié)中提挈出來的要點歸納起來，就形成了段落的中心思想。

［例5］

We visited the seals frolicking in the water． Then we paid a visit to the colorful birds in the big new birdhouse．After that we stopped for a coke and a hot dog．Before going home，we spent a lot of time watching the funny monkeys．

［分析］

1．What is the topic？Activities at the zoo．
2．What does the author want me to know about the topic？There are a variety of activities at the zoo．
3． What general statement expresses what the author wants me to know about the topic？ There is no general statement telling me this but I have inferred it．

以上主要介紹如何獲取段落的中心思想。由于段落和文章在結(jié)構(gòu)上極其相似，所以，確定文章的主題思想首先要找出文章中與段落主題句對應(yīng)的部分，即引言段。引 言段多位于文章的開頭部分。一般來講，引言段中有一個表現(xiàn)主題且具有概括性的句子，即破題句（thesis statement）。破題句多為引言段的最后一句話。找到它，該選文的主旨便一目了然了。