英文说明文写作方法总纲

分类法分类就是按照事物的不同特点将它们划成多个类别。

事物可以按照不同的标准进行分类，标准则取决于分类的成因。

例如，在分析某系学生的构成情况时，如果想了解他们的学习情况，可以将他们根据考试成绩划分为若干组；如果想研究是否有可能组织一场足球比赛或是篮球比赛，可以根据对足球和篮球的爱好程度把学生划分成若干组。

不管分类的目的是什么，分类的标准必须具有普适性和排他性，也就是说分类标准必须覆盖分类样本集中的所有样本元素，而且样本集中的任一元素只能隶属于分类标准项次中的唯一一项。

例如，把学生分成男生、女生和运动员是不合适的，这一标准违反了排他性原则，因为某个学生可能是男生的同时又是运动员，他占据了两个分类项次。

再如，把学生分成中学生和大学生在有些情况下也不一定合适，该标准违反了普适性原则，即有些学生既不是中学生也不是大学生（如小学生）。

表示分类的名词：种：kind, sort, type类：group, classification, category组成成员：member分部/分支：division/branch纲：class 目：order 科：family 属：genus 种：species表示分类的动词和动词短语：将……按……分类（排序）：class, classify, divide, categorize, group, place, arrange 属于某一类：belong to, fall into, be classed with包括若干类：there be, contain, consist of, comprise, include, be composed of, be comprised of组成……类：make up, constitute, composeE x e r c i s e s1. Read the following passages and discuss whether they follow the classification criterion of exclusiveness and inclusiveness.Passage 1:generation of electricity to meet the power and light needs of cities and industries. The other covers the application of small amounts of power for communication and various other purposes.Passage 2:We usually think of bees as being sociable insects which live in communities, but this is not always true. One way of classifying bees is by “social” and “solitary” species, and there are many of the latter. Bumble bees（野蜂）and honey bees are social species. Among solitary bees there are primitive wasplike bees, medium-sized solitary mining bees, so-called sweat bees, \carpenter bees and cuckoo bees.2. Read the following passage, and fill in the blanks with appropriate words.In Britain, state schools can be classified according to the age range of the pupils and the type of education provided. Basically, there are two types of schools: primary and secondary. Primary schools cater to（满足需要）children age 5-11 and secondary schools ages 11-16 (and up to 19). Primary schools can be sub-divided into infant schools (for age 5-7) and junior schools (for age 7-11). Secondary schools may be one type for all abilities, viz.（即）comprehensive schools; most secondary schools are of this kind. Alternatively, pupils may be grouped according to their ability and selected by means of an examination at age 11 (known as the“11-plus exam”). Thus, grammar schools cater to those with academic ability; modern schools for those with less academic ability; and technical schools for those with more practical skills.1) Schools _________________________________________ the pupils’ages and thetypes of education.2) There are ________________________________________ schools: primary andsecondary.3) Primary schools ___________________________________________ into infant andjunior schools.4) Secondary schools pupils ______________________________ their ability.5) The criterion（标准）for classifying secondary schools is whether or not there is______________________________.2. There are thousands of languages in the world. Languages are classified intodifferent families according to their common attributes. Do you know which family English belongs to? Below is a language tree proposed by German linguistic August Schleicher (1821-1868). Please describe it using the classification method:Proto-Indo-EuropeanWestern Branch Eastern BranchCeltic-Italic GermanicOld High German Old Saxon Old Low Fraconian Anglo-FrisianHigh German Low German Dutch Old English Old FrisianEnglish Frisian描述法（二）过程的描述既然有过程就必然有次序，关键在于搞清楚全过程的每一个步骤，再利用表示列举的衔接短语，按照过程的前后次序描述每一个步骤。

过程的描述往往按照时间顺序或过程的发展顺序进行描述。

1. 按照过程的发展顺序描述如果某个描述涉及到多个步骤，应该按照过程的发展顺序把这些步骤交代清楚。

既然完整的过程分为多个步骤，那么这些步骤的顺序则显得至关重要。

成功地按过程描述实际上告诉了读者如何去完成具体任务。

描述过程的常用衔接词和短语：1) Firstly … Secondly … Thirdly … Finally …2) First, Then, Next, After this, Lastly3) Afterward, Furthermore, Moreover, In addition to …2. 按照时间顺序描述在讲述故事或描述事件的时候，最简单同时也最清楚的方法是按照时间的顺序描述，也就是按照事情发生先后顺序，较早发生的事情在前面描述，较晚发生的事情在后面描述。

时间作为一个主线条可以为读者提供非常清楚的思路。

常用衔接词和短语：首环节：first, firstly, at first, first of all, in the first place, to begin with, one中间环节：second, secondly, in the second place, next, afterwards, after that, then, later, another, third, thirdly, still another, in addition, besides, furthermore 末环节：lastly, at last, finally, eventually, in the endE x e r c i s e sHow a New Road is Built__ (a) Though I had been on the train for more than thirty hours and spent a sleepless night, I didn’t feel tired at all, and I believed my days in Beijing would be as sunny as the skies. __ (b) Like other passengers, I began to collect my things, and put my mug, towel, atlas（地图册）, apples, and other things into my bag.__ (c) I walked out of the train and was carried forward by the stream of people into an underground passage and then into a big hall.__ (d) My heart gave a leap when I heard the announcement that our train would soon arrive at its destination --- Beijing.__ (e) As I stepped out of the station, I was dazzled（眩目）by the bright autumn skies of Beijing.__ (f) To the tune of a beautiful song the train pulled into the station and gently stopped by a platform.1. Please organize the following instructions into a coherent paragraph, and discuss the questions in the brackets.How to Deal with Snakebites in the Field1) Tie a handkerchief, necktie, or belt on your victim above the bite to prevent the bloodfrom flowing to the heart2) Decide whether to take the victim to the doctor or call for a doctor (How will you make adecision?)3) Remove the venoma. make cuts in a crisscross（十字）fashion on the bitten area, cutting about one fourthinch deep;b. suck out the blood and spit it out [Will you die if you swallow the blood?]4) Don’t give whiskey [Do you know why?]; you can give coffee or some other beverage tothe victim.5) Reassure the victim举例法一般来讲，概括性太宽泛的句子不具有太强的说服力，往往需要一点具体内容加以支持。