在上一讲我们讲了主题句，推展句的写法；这一讲我们要进一步来谈一谈段落发展的几种手段以及结尾段的写法。

　　段落发展的几种手段

　　1． 列举法(details)

　　作者运用列举法，是通过列举一系列的论据对topic sentence中摆出的论点进行广泛、全面地陈述或解释，列举的顺序可以按照所列各点内容的相对重要性、时间、空间等进行。

　　Yesterday was one of those awful days for me when everything I did went wrong. First, I didn't hear my alarm clock and arrived late for work. Then, I didn't read my diary properly and forgot to get to an important meeting with my boss. During the coffee break, I dropped my coffee cup and spoilt my new skirt. At lunch time, I left my purse on a bus and lost all the money that was in it. After lunch, my boss was angry because I hadn't gone to the meeting. Then I didn't notice a sign on a door that said "Wet Paint" and so I spoilt my jacket too. When I got home I couldn't get into my flat because I had left my key in my office. So I broke a window to get in and cut my hand.

　　根据本段主题句中的关键词组everything I did went wrong，作者列举了8点内容，分别由first, then, during the coffee break, after lunch time等连接词语引出，使得该文条理清楚、脉络分明、内容连贯。

　　常用于列举法的过渡连接词有：for one thing , for another, finally, besides, moreover, one another , still another, first, second, also等。

　　2. 举例法(example)

　　作者通过举出具体事例来阐述、说明主题句的内容，严格地讲，举例法也是列举法的一种，它们的区别在于：列举法侧重罗列事实，所列事实力求全面；而举例法侧重通过举出典型事例来解释作者观点，且事例可多可少。

　　我们来看下面这个用举例法展开的段落。

　　There are many different forms of exercises to suit different tastes. For example, those who enjoy competitive sports may take up ball games. For another example, if they prefer to exercise alone, they can have a run or take a walk in the morning or in the evening. Besides, people can go swimming in the summer and go skating in the winter. In short, no matter what their interests are, people can always find more than one sports that are suitable to them.

　　本段采用了三个事例来说明主题句中的关键词组different forms of exercises，这三个例子分别由连接词for example, for another example 和 besides引出，最后由引导的结尾句总结全段内容。

　　举例法中常用的连接词有：for example (instance), one example is, besides, furthermore, moreover, in addition等。

　　3. 叙述法(narration)

　　叙述法发展段落主要是按照事物本身的时间或空间的排列顺序，通过对一些特有过渡连接词的使用，有层次分步骤地表达主题句的一种写作手段。用这种方法展开段落，作者能够清楚连贯地交待事物的本末，从而可以使读者可以清晰、完整地理解文章的含义，例如：

　　In the flat opposite, a woman heard the noise outside. When she looked out through the window, she discovered that her neighbor was threatened by someone. She immediately called the police station. In answer to the call, a patrol police car arrived at the scene of the crime quickly. Three policemen went inside the flat at once, and others guarded outside the building to prevent anyone from escaping.

　　这段是按照事物发展的先后顺序，叙述从发现案情、报警、到警察赶到、包围现场的过程。全文脉络清晰，叙述的层次感强，结构紧凑。

　　常用于叙述法中的过渡连接词有：first, an the beginning, to start with, after that, later, then, afterwards, in the end, finally等。

　　4． 对比法或比较法(comparison & contrast)

　　将同类的事物按照某种特定的规则进行比较分析是一种常用的思维方法。通过对比，更容易阐述所述对象之间的异同和优缺点，例如：

　　The heart of an electronic computer lies in its vacuum tubes, or transistors. Its electronic circuits work a thousand times faster than the nicer cells in the human brain. A problem that might take a human being a long time to solve can be solved by a computer in one minute.

　　在这段文字上， 作者为了突出电子计算机运行速度之快，首先将它与人脑进行了比较， "-- a thousand times faster than --" ;而后，又将这一概念具体到了 "a problem"上，通过对比使读者从 "-- a long time -- in one minute"上有更加直观的认识。

　　常用于对本法或比较法上的过渡连接词有：than, compared with等。

　　5． 分类法(classification)

　　在阐述某一概念的段落中，常用分类法。通过对概念中所包括的事物进行分门别类，分别加以叙述，使读者有更为清晰的认识，如：

　　Ever since humans have lived on the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words and ideas. Tourists and the people unable to hear or speak have had to resort to this form of expression. Many of these symbols of whole words are very vivid and exact and can be used internationally; spelling, however, cannot. Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A nod signifies approval, while shaking the head indicates a negative reaction. Other forms of nonlinguistic language can be found in signal flags, Morse code, and picture signs.

　　在该段中为了说明topic sentence中的 "various forms of communication"，作者将其分为oral speech, sign language, body language及other forms of nonlinguistic language，并逐加阐述。

　　采用这种方法的段落并没有标志突出的连接词，所述各项均为平行并列关系，所以没有明显的主次之分。

　　6．　因果分析法(cause and effect)

　　在阐述某一现象的段落中，常采用因果分析法。例如：

　　The role of women in today's society is changing. One reason is that women have begun to assert themselves as independent people through the women's movement. Also, women are aware of the alternatives to staying at home. Another reason is that increasing numbers of women who enter new fields and interests serve as role models for other women. Moreover, men are becoming more conscious of the abilities of women and have begun to view their independence positively.

　　本段中，主题句提出了一种社会现象，推展句则对产生这种现象的原因作出各种解释。 常用于因果分析法的连接词有：because, so, as a result等。

　　7． 定义法(definition)

　　在科普文章的写作中，定义法是必不可少的。通过下定义，可以使读者对该事物有一个更直接的认识。

　　Automation refers to the introduction of electronic control and automation operation of productive machinery. It reduces the human factors, mental and physical, in production, and is designed to make possible the manufacture of more goods with fewer workers. The development of automation in American industry has been called the "Second Industrial Revolution".

　　这一段文字使我们了解了 "automation" 和 "Second Industrial Revolution" 两个概念，分别由 "refers to" 和 "been called" 引出。

　　常出现在定义法中的词语有：refer to, mean, call等。

　　8. 重复法(repetition)

　　句子的一部分反复出现在段落中，这就是重复法。它往往造成一种步步紧逼的气氛，使文章结构紧凑，有感染力。比如：

　　Since that time, which is far enough away from now, I have often thought that few people know what secrecy there is in the young, under terror. I was in mortal terror of the young man who wanted my heart and liver; I was in mortal terror of my interlocutor with the iron leg; I was in mortal terror of myself, from whom an awful promise had been extracted; --

　　该段中反复应用了I was in mortal terror of …我经常处于恐怖之中。

　　以上， 我们结合具体文章讨论了展开段落的几种方法。在实际写作中，我们往往不必拘泥于一种写作方法，而是将若干方法穿插在一起，使文章有声有色。

　　结尾段

　　我们知道文章的开头很重要，因为好的开头可以吸引读者、抓住读者的注意力。同样，文章的结尾也很重要，好的结尾会使读者对全文的中心思想留下深刻的印象，可以增添文章的效果和说服力，让人深思，回味无穷。确切地说，结尾的作用就是概括全文内容，进一步强调或肯定文章的中心思想，使读者加深印象；有时也用于展望未来，提出今后方向或令人深思的问题给读者留下回味和思考的余地。

　　但是，如何才能写好英文短文的结尾呢? 下面就介绍几种写结尾段最常用的方法：

　　1．重复中心思想: 回到文章开头阐明的中心思想或主题句上，达到再次肯定和强调的效果。

　　(例1)A sense of humor is really one of the keys to happiness. It gives zest to life to make it worth living.

　　(例2)With all these benefits, it is no wonder that sports and games have now become more popular with people than ever.

　　2．作出结论: 文章最后用几句话概括全文内容，并进一步肯定文章的中心思想或作者的观点。

　　(例1)In conclusion, a good teacher-student relationship can be mutual beneficial. The students gain knowledge eagerly and enjoyably, and the teacher gains satisfaction from his job.

　　(例2)On the whole there are more advantages than disadvantages in the use of TV. Yet different people may have different attitude toward TV. But we must realize that television in itself is neither good nor bad. Its value to people and society depends on how we look at it.

　　3．应用引语: 用格言、谚语或习语总结全文，既言简意赅又有更强的说服力。

　　(例1)If you have anything to do, try to do it yourself, for that is the safest way to

　　permanent success. Remember the famous saying. "God helps those who help themselves."

　　(例2)If we stick to studies day after day, there is nothing that can't be achieved. As an old saying goes: "Constant dropping of water wears away a stone."

　　4．用反问结尾: 虽然形式是问句，但意义却是肯定的，具有明显的强调作用，引起读者思考。

　　(例1)Therefore, listening skills must be consciously improved. Since it is such an important means of learning and communication, why should we not develop this ability as far as possible?

　　(例2)So，what can we benefit from wealth if we do not have health?

　　5．提出展望或期望: 表示对将来的展望或期待读者投入行动。

　　(例1)I am sure that Chinese will become one of the most important languages in the world in the next century. As China will open further to the outside world the language is sure to be spread world widely.

　　(例2) If everyone has developed good manners, people will form a more harmonious relation. If everyone behaves considerately towards others and social ethics people will live in a better world. With the general mood of society improved, there will be a progress of civilization.

　　以上介绍了几种写结尾段最常用的方法，但到底选择何种方法结尾还得根据文体来决定。平铺直叙的记叙文，往往在故事或事实情节讲完时文章也就自然结束了，而说理性和逻辑性较强的说明文和议论文都应有一个正式的结尾。希望以上介绍的几种方法能对大家写好结尾有所帮助。

　　首先，一个段落必须有一个中心即主题思想，该中心由主题句特别是其中的题旨来表达。整个段落必须紧扣这个主题(stick or hold to the topic)，这就是段落的统一性(unity)。其次，一个段落必须有若干推展句，使主题思想得到充分展开，从而给读者一个完整的感觉，这就是完整性(completeness or adequateness)。再者，一个段落不是杂乱无章的，而是有机的组合，句子的排列顺序必须合乎逻辑，从一个句子到另一个句子的过渡必须流畅(smooth)，这就是连贯性(coherence)。下面我们就对这三个标准分别加以说明。

　　1.　统一性

　　一个段落内的各个句子必须从属于一个中心，任何游离于中心思想之外的句子都是不可取的。请看下例：

　　Joe and I decided to take the long trip we'd always wanted across the country. We were like young kids buying our camper and stocking it with all the necessities of life. Bella bakes the best rhubarb pie. We started out in early spring from Minneapolis and headed west across the northern part of the country. We both enjoyed those people we met at the trailer park. Joe received a watch at his retirement dinner. To our surprise, we found that we liked the warm southern regions very much, and so we decided to stay here in New Mexico.

　　本段的主题句是段首句，controlling idea（中心思想）是take the long trip across the country。文中出现两个irrelevant sentences，一个是Bella bakes the best rhubarb pie，这一段是讲的是Joe and I，中间出现一个Bella是不合适的。还有，Joe received a watch at his retirement dinner这一句更是与主题句不相关。考生在四级统考的作文卷上常常因为造出irrelevant sentences（不相关语句）而丢分，值得引起注意。再看一个例子：

　　My name is Roseanna, and I like to keep physically fit. I used to weigh two hundred pounds, but I joined the YMCA for an exercise class and diet program. In one year I lost eighty pounds. I feel much better and never want to have that much weight on my five-feet frame again. I bought two new suitcases last week. Every day I practice jogging three miles, swimming fifteen laps, lifting twenty-pound weights and playing tennis for one hour. My mother was a premature baby.

　　本段的controlling idea 是like to deep physically fit，但段中有两个irrelevant sentences，一个是I bought two new suitcases last week，另一个是My mother was a premature baby。

　　从上面两个例子可以看出，native speakers同样会造出来irrelevant sentences。卷面上如果这种句子多了，造成偏题或离题，那问题就更严重了。