四级和六级考试写作虽然曾经采用相同的命题，但是评分却有差别。在写作测试和教学中，考生和教师都应该敏锐地把握这些差异。具体地讲，语汇、语型、句法和章法结构多个方面在深度和准确程度上有差异。
实际上不同的考试使用相同或者相似的命题，在国外测试中屡见不鲜。托福和雅思，GMAT 和GRE命题很多时候是相同的。可是考试的评分重点有很大的不同。
写四级作文，考生应该注意不要超过四级考试的词汇范围。句法结构要有适当的变化，但是不要使用过于复杂的从句。否则，错误的复杂句子远远不如正确的简单的句子。
我们用一道具体的题目分析四级和六级的差别。
例题：1998年1月
Part Ⅴ Writing (30 minutes)
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Harmfulness of Fake Commodities. You should write at least 100 words and you should base your composition on the outline (given in Chinese) below:
1. 目前社会上有不少假冒伪劣商品(fake commodities)。为什么会有这种现象?
2. 举例说明假冒伪劣商品对消费者个人、社会等的危害。
Harmfulness of Fake Commodities
范文一
Each individual encounters such troubles as sickness and discomfort situations in his or her development. Similarly, each society is inevitably harmfully impacted by immoral or even illegal economic activities in the process of its evolvement. The most notorious and harmful among these despicable actives are fake commodities.
Fake commodities, like a virus that intrudes and cripples an organism, exert alarmingly detrimental influences on each individual consumer, the community, and the social mores as well.
They directly hurt the consumers by providing products that are priced highly but inferior in quality. Sometimes such products as faked medicine or foods can threaten consumers’ life, needless to mention consumers’ economic loss. The more fake commodities a society has, the more exacerbated the moral and ethic in that society.
What the society must immediately address is to minimize the quantity of any fake commodities and eradicate any opportunity to manufacture them. 146 words 注意现在的作文要求字数增加到了200字左右。
讲评：
1. 类比性思维和写作手法处理抽象复杂的命题
2. 比较结构的句型写作训练
3. 主语从句为代表的复杂句法结构
4. 定语从句的训练
范文二 204单词
Economic boom should bring people a more comfortable and convenient life. Ironically, the more commodities available in a society whose economic fabric is not woven by legal and moral warp and woof , the less and less security the average consumers can have. In fact, even today the public is still jeopardized by fake commodities that flood almost each developing country.
Fake commodities directly harm the average individual consumers in a series of ways. First they are usually inferior in quality and thus cannot meet consumers’ ends. Take a fake watch as an example, it is sold at the same price as is the genuine one but seldom can it give time precisely. Secondly, they might threaten consumers’ health ?and life in case of fake foods, medicine, and beverages. Some patients are seriously endangered by taking fake medicines. Some even lose their life immediately after eating fake soybean sauces and vinegar. The society as a whole is also detrimentally infected by fake commodities as far as the moral and ethic is concerned.
Then, how to address this serious problem? Most vital is to legally penalize those who manufacture and trade fake products. Second is to educate people how to tell the facts and fiction.
以上两篇作文都是非常优秀的。从用词到句型的变化，章法的合理安排等各个方面都已经超越了一个考生能够掌握的程度。所以，单纯从四六级考试来看，都不是适合学生的作文。那么考虑到考生的实际英语水平。我们提供一下两种写法。
究竟什么才是优秀的四级作文呢？这个说法本来就比较矛盾。因为四级考试本身就是要求比较低的英文。如何在低层次获得“优秀”实在不是一件容易的事情。
分析：
1. 目前社会上有不少假冒伪劣商品(fake commodities)。为什么会有这种现象?
2. 举例说明假冒伪劣商品对消费者个人、社会等的危害。
这个考题要求考生
> 描述社会上有不少假冒伪劣的商品
> 分析社会现象存在的原因
> 利弊陈述
这是四级和六级共同要求的语言功能，这两种考试都要求考生严格按照命题的提纲写作。所以三个段落的划分就十分清楚。
范文三 （四级）
190 words
The society has hundreds and thousands of fake commodities. They are almost everywhere. They are in daily life, hospital, supermarkets, and so on.
Why do we have these fake commodities? This question has not only attracted the interests from the scientists but also from the general public. Generally three reasons have been given to explain this phenomenon. First of all, fake commodities are usually profitable. They are lower in cost and of course, in quality, but are high in price. Secondly, the society often finds it hard to help consumers to tell fake ones from the genuine goods. Third, legal restrictions against fake commodities are not work at all or work with lower efficiency.
Fake commodities do harm to the human life. They can damage the life or ruin one’s happiness, depending on what kind of fake commodities consumers have bought. They can also damage the society as a whole if the fake commodities are not restricted by governments or other agencies. Fake medicines are a typical example. Today, even in the field of academic, fake papers are not uncommon. All these fake commodities exert negative impacts on human civilization.
范文四 （六级）： 258 words
Fake commodities seem to flood into each corner of daily life. Worse they even stream into academic institutions evidenced by the fact that some professors plagiarize papers. We have fake clothes with brand name. We have fake medicines which are openly sold in hospitals. We also have some fake computers and TV sets. In one word, fake commodities are almost everywhere.
Then we naturally ask: Why do fake commodities flow into the supermarkets? The flood is so overwhelming that both the sociologists and the general public have to dig the root reasons. On the basis of scientific research and survey, scholars discover that among the diverse array of contributing factors, the major one is that the society in which the fake commodities are flooding is usually short of an effective legal system to control or guide the markets. Another reason, similarly vital, states that the social and economic order is maintained by, to a considerable extent, ethic and moral. But the moral and value system becomes fragile when subject to a market characterized and dominated by the cold cash. Economic models have been put forward to provide theories to account fro why fake commodities can negative influence a society to such an extent. Of courses many other reasons also play their roles.
，英语六级写作命题相同评分不同