2.舉例法(example)
作者通過舉出具體事例來闡述、說明主題句內容。嚴格地講，舉例法也是列舉法的一種，它們區別在於：列舉法側重羅列事實，所列事實力求全麵；而舉例法側重通過舉出典型事例來解釋作者觀點，且事例可多可少。我們看下麵這個舉例法如何展開段落：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 exercises alone， they can have a run or take a walk in the morning or in the evening. Besides， people can go swimming and go skating in the winter. In short， no matter what their interests are， people can find more than one sports that are suitable to them .
本段采用了三個事例來說明主題句中關鍵詞組different forms of exercises， 這三個例子分別由連接詞for example， for another example 和besides 引出，最後由結論句總結全段內容。常用連接詞有for example， for instance， one example is， besides等。
3.敘述法(narration)
敘述法發展段落主要是按照事物本身時間或空間排列順序，通過對一些特有過渡連接詞使用，有層次分步驟地表達主題句的一種寫作手段。用這種方法展開段落，作者能夠清除連貫地交待事物本末，從而使讀者可以清晰、完整地理解文章含義。例如：In the flat opposite， a woman heard the noise outside. Then she looked out through the indoor， 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.
這段是按照事物發展先後順序，敘述從發現案情、報警、到警察趕到、保衛現場等過程。全文脈絡清晰，敘述層次感強，結構緊湊。常用的連接詞有first ，at the beginning， to start with， after that， then， afterwards， in the end， finally 等。
4.對比法或比較法( comparison / contrast)
將同類事物按照某種特定規則進行比較分析是一種常用的思維方法。通過對比，更容易闡述所述對象之間的異同和優缺點。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.
在這一段落中，作者為了突出電子計算機運行速度之快，首先將它與人腦進行了比較，用了 a thousand times faster than；而後，又將這一概念具體到a problem上，使讀者通過a long time和in one minute的對比能更加直觀認識。
常用的過渡詞有than， compared with， furthermore， moreover， in addition 等。
5.分類法(classification)
在闡述某一概念段落中，常用分類法。通過對概念中所包括事物進行分門別類，分別加以敘述，使讀者能有清晰的認識。例如：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. Then 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 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 .
在這段中為了說明 various forms of communication這一主題，作者將其分為 oral speech， sign language， body language 及other forms of nonlinguistic language ，並逐個加以闡述。
6.因果分析法(cause and effect)
在闡述某一現象段落中，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 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 the fields and interests serve as models for other women. Moreover， men are becoming more conscious of the abilities of women and have begun to see their independence positively.
本段中，主題句提出了一種社會現象，拓展句則對產生這種現象原因做出各種解釋。常用的連接詞有because， so， as a result 等。
7.定義法(definition)
在科普文章寫作中，定義法必不可少。通過下定義，可以使讀者對該事物有一個更直接認識。
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 the has been called theSecond Industrial Revolution.