第二天：段落的构成要素
段落是由若干个彼此关联的句子构成的，通常用以表达一个中心思想或者从一个角度对
pet30a文章的主题进行阐述。因此，段落不能是一组句子的任意堆砌，而是符合一定的模式，文章的主题进行阐述。因此，段落不能是一组句子的任意堆砌，而是符合一定的模式，具有具有
某些基本特征，遵循一定段落发展方法的。某些基本特征，遵循一定段落发展方法的。
当然, 段落并没有固定的模式。在实践中，我们常常碰到各种各样的段落，有些仅仅充当导
言或结束语，有些仅仅起过渡词作用，这种段落便不可能也不必要包含完整的思想内容。这种段落便不可能也不必要包含完整的思想内容。要要
写出一篇好文章，我们就必须了解一些结构完整的段落的写法，掌握一点组句成段的基本知
识。识。
结构完整的段落大多由三部分组成：完整的段落大多由三部分组成：
一、主题句一、主题句
主题句是概括段落中心思想，反映作者写作意图的一个概括性的句子，是段落的核心所
在。所以，写好主题句是写好一个段落的前提。在。所以，写好主题句是写好一个段落的前提。
1.段落主题句的位置及其作用段落主题句的位置及其作用
主题句通常由主题和作者的观点两部分组成，作为段落传递信息的出发点，简明扼要地告
诉读者段落的线索和范围。但是，主题句的位置并不是固定不变的，它可以位于段首，诉读者段落的线索和范围。但是，主题句的位置并不是固定不变的，它可以位于段首，也可也可
以位于段中、段尾。以位于段中、段尾。主题句位于段首的情况比较多见。段首主题句开门见山，直接点明段落主题句位于段首的情况比较多见。段首主题句开门见山，直接点明段落
主题，有助于确定段落的主线，有助于确定段落的主线，使各个发展句围绕段落主题自然展开；使各个发展句围绕段落主题自然展开；使各个发展句围绕段落主题自然展开；段尾主题句具有结论段尾主题句具有结论
作用，是对前面句子的归纳总结。作用，是对前面句子的归纳总结。
请看下面各例：请看下面各例：
Public Public opinions opinions opinions on on on what what what it it it takes takes takes to to to succeed succeed succeed in in in one’s one’s one’s studies studies studies or or or career career career vary vary vary widely. widely. Given
approximately approximately equal equal equal circumstances, circumstances, circumstances, some some some claim claim claim the the the success success success factor factor factor is is largely largely a a matter matter of of of luck luck luck——
being in the right place and the right time. Others speak of utter devotion to work, combined with a a degree degree degree of of of ruthlessness. ruthlessness. ruthlessness. Still Still Still others others others maintain maintain maintain that that that it it it is is is undoubtedly undoubtedly undoubtedly a a a matter matter matter of of of how how how much much 纯碱是小苏打吗
舜字怎么读intelligence intelligence you you you have have have or or or simply simply simply how how how much much much education your education your mother mother had. had. had. In In In a a word, word, people have people have
different ideas on it.
本段的主题句Public Public opini
opini opinions ons ons on on on what what what it it it takes takes takes to to to succeed succeed succeed in in in one’s one’s one’s studies studies studies or or or career career career vary vary widely.放在段落的开头，放在段落的开头，开门见山地点明主题，开门见山地点明主题，开门见山地点明主题，使读者很容易抓住本段的写作主线：使读者很容易抓住本段的写作主线：使读者很容易抓住本段的写作主线：对学业对学业
三只小猪学英语或事业成功所持的各种不同的观点和看法。或事业成功所持的各种不同的观点和看法。
The purpo of this book is to provide you with practice in spelling English. It is not a book that
treats the complex rules of English orthography. Neither does it teach you how to u a dictionary. Its main objective is to introduce regular spelling patterns: that is, to prent a regular system for spelling spelling a a a large large large group group group of of of words. words. words. By By By learning learning learning the the the patterns, patterns, patterns, and and and by by by practicing practicing practicing them, them, them, you you you will will
master thousands of words.
Only the idle will be tired.
只有闲人才会感到疲倦。只有闲人才会感到疲倦。 本段的主题句The purpo of this book is to provide you with
practice practice in in in spelling spelling spelling English English 也是放在段落的开头，直截了当地告诉读者作者的写作意图，使
读者对本段的主题思想有了明确的认识。读者对本段的主题思想有了明确的认识。
Give students a chance to grow. Do you mold them from one of a thousand patterns? Let them ek knowledge, but do not find it for them. Let them learn patience; do not force it on them. Let them take their own time to grow; do not t rigid time schedules. Most of all, do not push them against against a a a stone stone stone wall, wall, wall, crushing crushing crushing them them them with with with knowledge knowledge knowledge gained gained gained from from from the the the experience experience experience of of of others. others.
Experience cannot be taught; it must come slowly through personal arch.
在这个段落中，在这个段落中，主题句先不出现，主题句先不出现，主题句先不出现，而是先举出许
多具体的而是先举出许多具体的experiences ，在段落结尾时才予以
归纳，得出中心结论：
Experience cannot be taught; it must come slowly through personal arch.这样的段落结构一开始容易使读者产生悬念，从而收到特殊的表达效果。这样的段落结构一开始容易使读者产生悬念，从而收到特殊的表达效果。
Most of us may have such experiences: when you go to some place far away from the city you live in and think you know nobody there, you are surprid to find that you should run into one of your old cla ssmates in the street. Perhaps both of you would cry out, “What a small world!”
在这个段落里，在这个段落里， 作者先给出了一个假设性的事例，吸引读者的注意力，然后在段落结束时
总结出“What a small world!”（“世界真小啊”）作为段落主题句。这样的段落有感染力，使读
者有兴趣读下去。者有兴趣读下去。
但是，主题句有时也可能出现在段落中间，主题句有时也可能出现在段落中间，或者根本就没有明显的段落主题句。或者根本就没有明显的段落主题句。或者根本就没有明显的段落主题句。在下面的例在下面的例
子中主题句是在段落中间出现的。这种情况比较少见。子中主题句是在段落中间出现的。这种情况比较少见。
Californians and New Englanders are both American. They speak the same language and abide by the same federal laws. Bu t 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.
有时为了特别强调主题句的内容，也可以使主题句既出现在段首，又出现在段末。如：有时为了特别强调主题句的内容，也可以使主题句既出现在段首，又出现在段末。如：
Good manners are important in all countries, but ways of expressing good manners are different
from from country country country to to to country. country. country. Americans Americans Americans eat eat eat with with with knives knives knives and and and forks; forks; forks; Japane Japane Japane eat eat eat with with with chopsticks. chopsticks.
Americans say “Hi” when they meet; Japane bow. Man y American men open doors for women; Japane Japane men men men do do do not. not. not. On On On the the the surface, surface, surface, it it it appears appears appears that that that good good good manners manners manners in in in America America America are are are not not not good good
manners manners in in in Japan, Japan, Japan, and and and in in in a a a way way way this this this is is is true. true. true. But But But in in in any any any country, country, country, the the the only only only manners manners manners that that that are are
important are tho involving one person’s behavior toward another person. In all countries it is good manners to behave considerately toward others and bad manners not to. It is only the way of behaving politely that differs from country to country.
而下面这段话则没有明显的主题句。而下面这段话则没有明显的主题句。
An An independent independent independent trucker trucker trucker working working working full full full time time time can can can earn earn earn clo clo clo to to to $20,000 $20,000 $20,000 gross gross gross compared compared compared with with with the the
$30,000 or more that a union trucker makes. A union trucker works a 10 hour shift an d that’s it,
whereas the independent trucker is always pushing himlf. And even though there are strict laws prohibiting a trucker from driving more than ten hours a day, with four hours on and four hours off, no independent trucker adheres to that — becau if he did, he’d never get the load delivered on 接开头的成语
time. With the economy as shaky as it is, the competition for loads is fierce and, at times, vicious. There are only so many loads, and truckers will bid on them, the lowest bid getting the load. 这段话的主题句应该是这段话的主题句应该是 “An independent trucker has a difficult time making a living.”
但由于暗含的意思很清楚，所以被省去。应该注意的是，在没有主题句的段落中，叙述应该十分清楚，
暗含的主题必须显而易见。暗含的主题必须显而易见。
There are two tragedies in life. One is to lo your heart’s desire, the other is to gain it.
94属什么失去心中所欲的和得到心中所欲的，失去心中所欲的和得到心中所欲的，是人生的两大悲剧。是人生的两大悲剧。是人生的两大悲剧。特别提请注意的是，在段落中，虽特别提请注意的是，在段落中，虽
然主题句可以放在不同的位置，但最常见的还是放在段首，这并不是说主题句一定就是该段
的第一句话，而往往是在主题句之前还有一个承上启下的过渡句。的第一句话，而往往是在主题句之前还有一个承上启下的过渡句。
2.段落主题句的写作方法段落主题句的写作方法
主题句的作用是要告诉读者该段的主题思想，主题句的作用是要告诉读者该段的主题思想，该段将围绕这个主题思想逐步展开、该段将围绕这个主题思想逐步展开、该段将围绕这个主题思想逐步展开、定义、定义、论
述、分类、解释和举例说明等，所以，段落主题句中必须包含一个主导思想，这是一个等待
发展的思想，也是段落的主旨所在。同时，段落主题句不能写得太笼统，也不能涉及面太窄。
一个段落的容量是有限的，如果主题句限定范围太宽，其内容就无法在一个段落中阐述清楚；
如果限定范围太窄又不利于段落的发展。段落主题句所限定的内容必须符合段落写作的目
的，有助于段落的铺开和抒发。例如：的，有助于段落的铺开和抒发。例如：
T elevision elevision is is very very important. important. 这个句子太泛，没有表达一个清楚的主题思想，做主题句不大
合适。可以改为：Television plays an educational role in our daily life.
Big cities have traf fic problems.这个句子如果用做主题句也没有表达出明确的主题思想，
这个句子如果用做主题句也没有表达出明确的主题思想，范围限得过宽，抓不住段落主线，不好下笔扩展段落。可改为：Traffic problems in big cities are rious, which can be found in veral ways.
He encountered an old friend yesterday.这是一个描写细节的句子。由于涉及面太窄而不利于展
开讨论，不适合做主题句。开讨论，不适合做主题句。
I go to college to make friends.如果作为段落的主题句就显得范围太窄了，作者发挥的余地太
小，段落不容易写好。可改为：Going to college, I can learn more and make new friends.
首页不同二、扩展句二、扩展句
扩展句是用来支持或说明主题句的，扩展句是用来支持或说明主题句的，是段落主题句的延伸和发展，是段落主题句的延伸和发展，是段落主题句的延伸和发展，起着辅助主题句、起着辅助主题句、推展段
落中心的作用，对主题句表达的中心思想或举例说明、或细致描写、或详细解释阐述和论证，
使读者能够清晰地理解和信服地接受作者所表达的意思。使读者能够清晰地理解和信服地接受作者所表达的意思。
扩展句一般要具备这样的特点：（1）清晰、详实，有较强的说服力，能清楚地表达思想；（2）
条理分明，条理分明，脉络清晰。上一句要为下一句铺平道路，下一句是上一句的自然延伸，脉络清
晰。上一句要为下一句铺平道路，下一句是上一句的自然延伸，脉络清晰。上一句要为下一句铺平道路，下一句是上一句的自然延伸，一步一步一步一步
地论述或叙述主题。地论述或叙述主题。
一个段落通常有若干个扩展句。一个段落通常有若干个扩展句。这些扩展句可以处于同一个层次，这些扩展句可以处于同一个层次，这些扩展句可以处于同一个层次，共同来为主题句服务；共同来为主题句服务；也
可以在一级扩展句之下用二级扩展句来支持一级扩展句，从而构成扩展句之间的层次关系。
但在段落中如果有多个不同层次的扩展句时，必须要合理地安排它们，既要作到简洁清晰、
意义连贯、合乎逻辑，又要作到层次分明并紧紧地围绕主题句，为主题句服务；同时还要
注意一级扩展句、注意一级扩展句、二级扩展句等和主题句之间的关系。二级扩展句等和主题句之间的关系。二级扩展句等和主题句之间的关系。一级扩展句为主题句服务，一级扩展句为主题句服务，一级扩展句为主题句服务，二级扩展二级扩展
句支持一级扩展句来说明或论证主题句。句支持一级扩展句来说明或论证主题句。
高级ppt
Strong in action, gentle in method.——行动要坚强，方式要温和。请看下面的例子：行动要坚强，方式要温和。请看下面的例子：
（1）Money spent on advertising is money spent as well as any I know of. （2）It rves directly
to assist a rapid distribution of goods at reasonable prices thereby establishing a firm home market and so making it possible to provide for export at competitive prices. （3）
By drawing attention to new ideas, it helps enormously to rai standards of living. （4）
By helping to incr ea demand, it ensures an incread need for labor, and is therefore an effective way to fight unemployment. （5）
It It lowers lowers lowers the the the costs costs of of many many many rvices: rvices: rvices: without without without advertiments advertiments advertiments your your your daily daily daily newspapers newspapers newspapers would would would cost cost
four times as much, the price of your television licen would need to be doubled, and travel by bus or tube would cost 20 percent more.
这个段落中的句（1）是段落主题句，提出观点：
“花钱做广告是我所知道的最好的花钱方式。句（2）、（3）、（4）和（5）都是扩展句，处在同一层次上，进一步阐述和说明主题句，即通
过列举广告给社会带来的好处来说明为什么花钱做广告是最好的花钱方式。过列举广告给社会带来的好处来说明为什么花钱做广告是最好的花钱方式。
(1)The (1)The computer computer computer finds finds finds many many many applications applications applications in in in all all all fields. fields. fields. (2)Computers (2)Computers (2)Computers are are are now now now doing doing doing almost almost everything everything from from from diagnosing diagnosing diagnosing hospital hospital hospital patients patients patients to to to running running running nuclear nuclear nuclear pow pow er er stations. stations. stations. (3)In (3)In (3)In any any any field field
where information is collected, procesd, stored, and retrieved, computers are being ud more and more. (4)Computers are also ud as an aid to design planning. (5)For example, they can be ud to predict faults in design as well as the cost of a design if one is planning to build a road. 在这个段落中，句（1）是主题句，提出计算机在所有领域都有应用的观
点；句（2）、（3）
和（4）是一级扩展句，是一级扩展句，都支持和说明句都支持和说明句都支持和说明句（（1），具体说明计算机都在哪些领域应用，具体说明计算机都在哪些领域应用，而句而句（5）是二级扩展句，用来补充说明句（4），通过举例来说明计算机辅助设计的用途。，通过举例来说明计算机辅助设计的用途。
(1)In (1)In rock rock rock music music music there there there is is is a a a distinct distinct distinct and and and almost almost almost overwhelming overwhelming beat. beat. (2)No (2)No (2)No single single single beat beat beat is is
characteristic of the music today. （3）
But each song has an easily recognizable rhythm. (4)As you listen listen to to to a a a song, song, song, your your your foot foot foot usually usually usually starts starts starts to to to pick pick pick up up up the the the beat. beat. beat. (5)Before (5)Before (5)Before long, long, long, your your your entire entire entire body body
ems to be moving with it. （6）
Y our head pounds with the beat, and there is no room for thought. （7）Only the surge of the music is important. (8)In its own way, rock music is as dominant as the rock Gibraltar. Its message is an overgrowing emotional one.
在这一段中，句（1）是段落主题句，点出本段主题思想，要说明“摇滚乐最突出的特点是其
节奏”。句（2）、（3）是一级扩展句，对主题句进一步补充说明；而句（4）、（5）、（6）是二
级扩展句，从属于句（2），对句（2）起着补充、解释和说明的作用，更形象、生动地证明
了主题句所表达的思想。这里，句（7）是结尾句，它的功用在后面的章节里会做详尽的讲
解。解。
He who mistrusts most should be trusted least.——最不信任别人的人最不应该得到信任。最不信任别人的人最不应该得到信任。
三、结尾句三、结尾句
结尾句位于段落的末尾，在段落中也起着非常重要的作用，在段落中也起着非常重要的作用，用以对全段内容进行总结、用以对全段内容进行总结、用以对全段内容进行总结、归纳归纳
或提出结论性的观点。或提出结论性的观点。结尾句常和主题句相呼应，结尾句常和主题句相呼应，以不同的形式再现主题，并与扩展句相关
联。但是并非任何段落都必须有结尾句才算完整。但是并非任何段落都必须有结尾句才算完整。有的段落，有的段落，尤其是一些较短的段落中只有
主题句没有结尾句。主题句没有结尾句。
请看下面各段落中结尾句的写法：请看下面各段落中结尾句的写法：
Scientists Scientists believe believe believe that that that there there there has has has been been been life life life of of of some some some sort sort sort on on on the the the earth earth earth for for for about about about twelve twelve twelve hundred hundred
