最近在批改学生作文时，老师普遍有一种感觉：学生的作文大多用词简单、结构松散，从语体角度分析，正式程度都较低，呈口语化的倾向。以2009年的大作文为例，该作文为图画作文，图画是一张蜘蛛网上有很多人上网。图画中的中文提示词为：互联网的“远与近”，题目给出的要求是考生简要描述图画，阐明其含义，并发表评论。很多同学在写作时都忽略了大作文对正式文体的要求。正式文体与非正式文体的区别表现在用词、语法上。为了更好地说明这两种文体在语言特征上的区别，老师特意选择了考生大作文中普遍存在的非正式用语，并给出相应的正式用语进行比较。
两种文体在语言特征上的主要差异首先表现在用词上，体现在以下几个方面：
1.正式文体常使用正式用语，非正式文体则常使用非正式用语，这两类不同的用语是在长期的使用过程中被约定俗成地固定下来的。比如以下非正式用语一栏中的词汇在考生大作文中普遍存在，可修改为右栏正式用语中的表达：
| 非正式用语 | 正式用语 |
| crime | offense |
| people | individuals |
| cut down | reduce |
| serious | severe/grave |
| harm | damage(or destroy/undermine/jeopardise) |
| job | position |
具体而言，源于法语、拉丁语、希腊语的词语多用于正式文体；源于古英语的词语则多用于非正式文体。试比较：
We should investigate the root cause of the problem。
We should look into the root cause of the problem。
Investigate源于拉丁语，属正式文体用语，而look into是古英语词汇成分，属非正式文体用语。
2. 现代英语中的缩略词及缩约词多用于非正式文体，其相应的非缩略或非缩约形式则常出现在正式文体中。很多考生都忽略了这一区别，以下非正式用语栏中的表达都是从考生大作文中选出的，可修改为右栏正式用语中的表达。
| 缩略词 | 正式用语 | 缩约词 | 正式用语 |
| ad | advertisement | shouldn’t | should not |
| phone | telephone | won’t | will not |
| TV | television | there’s | there is |
| e.g。 | for example | don’t | do not |
| paper | newspaper | I’ve | I have |
| PC | personal computer | they’re | they are |
3. 很多考生使用了很多短语动词，而这正是非正式文体的一大特征，正式文体则常用与之同义的单个动词。试比较：
Informl: People can’t put up with the alienation brought by the Internet。
Formal: Individuals cannot tolerate the alienation brought by the Internet。
Informal: In this day and age, many people can make use of the Internet via computers or mobile phones。
Formal: In this day and age, many individuals can utilise the Internet via computers or mobile phones。
两种文体在语言特征上的第二类主要差异体现在语法上，具体包括以下几个方面：
1. 在构成比较句型时，很多考生选择使用了人称代词的宾格形式，其实使用人称代词的主格形式要显得更正式些。
Informal: He spent more time playing computer games than me。
Formal: He spent more time playing computer games than I。
2. 在表达“让步”概念时，很多考生选择使用的but, anyway, all the same, though, although等为非正式文体常用词语表达。正式文体则常使用yet, however, nevertheless, in spite of (despite)， notwithstanding等词语，
Informal: He tried to overcome his addiction to the Internet, but he failed。
Formal: He endeavoured to overcome his addiction to the Internet; however, it turned out to be a failure。
3. 在构成“方式状语”时，很多考生偏爱使用副词，而这正是非正式文体常用的表达方式，正式文体则常用介词和与该副词同根的词构成的介词短语：
Informal: It’s very important to…。
Formal: It is of great importance to…。
4. 在表达“原因”、“后果”等概念时，很多考生由于水平所限，总是使用非正式文体常用的so, because或其他形式的表示原因的从句，正式文体则常用 on account of, accordingly, thus, hence, consequently, owing to (the fact that…)等词或词组，且比较经常地运用分词短语、独立主格结构等。
Informal: Since computers had proliferated, many people become addicted to the Internet。
Formal: Computers having proliferated, many people become addicted to the Internet。
5. 在构成表示“目的”的状语时，很多考生使用具有非正式文体色彩的so as to；其实，用in order that引导的目的状语从句常出现于正式文体中：
Informal: We should do more outdoor activities so as to enrich our life。
Formal: We should do more outdoor activities in order that our life gets enriched。
6. 很多考生不会使用由引导词it引导的句子(如it is said that…)，实际上，这一结构多见于正式文体，不用这一结构而表达同一意义的句子多见于非正式文体： Informal: The number of students in the classroom has been going down。 Formal: It has been noted with concern that the number of students attending class has been declining alarmingly。
7. 很多考生省略关系代词、连词、介词，这些情况多见于非正式文体。
Informal: He flunked many courses. He had been expelled from the college。 Formal: He flunked so many courses that he had been expelled from the college。
Informal: He dealt with the problem the way his classmates does。
Formal: He dealt with the problem in the way his classmates does。
Informal: We should prevent it going from bad to worse。
Formal: We should prevent it from going from bad to worse。
8. 在表达“请求某人做某事时”，很多考生选择使用具有非正式文体色彩的主动语态句式，而没有使用具有正式文体色彩的被动语态句式。
Informal: Please communicate more with your friends and family。
Formal: More communication with your friends and family is needed。
9. 很多考生未能正确使用某些不定代词、动名词的复合结构，不太注意句子的主谓一致，未能体现文章的正式文体风格。
Informal: Everybody should look after themselves。
Formal: Everybody should look after himself。
Informal: Everyone should do their best。
Formal: Everyone should do his best。
Informal: I’m not surprised at him failing the course。
Formal: I am not surprised at his failing the course。