Expository Essay顾名思义就是说明文，可能写手小伙伴们在国内学习的时候肯定写过这类作文，但是到了国外留学遇到Expository Essay应该怎么写呢？有哪些写作注意事项呢？下文中给大家一一介绍，希望能帮助大家学会写Expository Essay.
Expository Essay的定义
Expository writing is a type of writing that is used to explain,describe,give information,or inform.The text is organized around one topic and developed according to a pattern or combination of patterns.The writer of an expository text cannot assume that the reader or listener has prior knowledge or prior understanding of the topic that is being discussed.
说明文是一种用来解释、描述、提供信息或通知大众的文体。文章应围绕着一个主题进行组织，并根据一种或多种模式展开。
关于人称
Second-person pronouns may be used in such writing,if needed.For example,in a how-to essay a writer may choose to personalize the instructions with"you".However,the use of first-person pronouns should be avoided.Expository essays will not reveal the opinion of the writer.
提示：如有需要，文中可使用第二人称代词。同时应尽量避免第一人称的使用，因为该文体不应反映作者的个人观点。
主要形式
Expository writing appears in and is not limited to letters,newsletters,definitions,instructions,guidebooks,catalogues,newspaper articles,magazine,articles,pamphlets,reports and research papers.
文章特点
---Focus:main topic
---Logical supporting facts including details,explanations,and examples
---Strong organization and logical order
---Clarity,unity and coherence
简而言之，就是要保证内容的科学性、说明的条理性和语言的准确性
写作方法
Since clarity requires strong organization,one of the most important mechanisms to improve skills in exposition is to improve the organization of the text.The patterns shown below are frequently used to create an expository essay.Additionally,more than one pattern may be used within an expository essay.
要学习说明文的写作，就必须在文章组织结构和说明方法上下功夫，下面的写作模式可能对你有所帮助。
1.描述法
The author describes a topic by listing characteristics,features,and examples.Cue words include“for example,characteristics are”,etc.
通过列举特点或者举例来进行描述。
2.Sequence顺序法
The author lists items or events in numerical or chronological order.Cue words include“first,second,third;next;then;finally”,etc.
使用数学或者时间顺序来列举事实。
3.Comparison比较法
The author explains how two or more things are alike and/or how they are different.Cue words include“different,in contrast,alike,same as,on the other hand”,etc.
解释两个（及以上）的事物之间有何相似和不同。
4.Cause and Effect因果法
The author lists one or more causes and the resulting effect or effects.Cue words include“reasons why,if...then,as a result,therefore,because”,etc.
列举一个或多个原因及其导致的结果。
5.Problem and Solution问题及解决方案法
The author states a problem and lists one or more solutions for the problem.A variation of this pattern is the question-and-answer format in which the author poses a question and then answers it.Cue words include“problem is,dilemma is,puzzle is solved”,etc.
陈述一个问题并列举一个或多个解决方案。可使用问答法。