句子是构成文章的基本框架。如何写出流畅、漂亮的句子是决定整篇文章是否成功的关键。学生在学习大学英语的过程中，对长句的表达或多或少都有了一定的理解，但是在写作的过程中却依然存在着句型结构过于简单，词汇运用过于局限的情况。因此，如何使句子在正确的基础上增强表现力，是学生们急于解决的问题。关于如何写出经典句型，我们可以从以下几个方面适当地改变：
1. 句型要丰富多彩，不要使用只有主谓宾、定状补的简单句型结构，也不能总使用There be 句型。
2. 可以尝试使用倒装句型，包括介词短语提前、时间状语提前、副词提前等。
3. 可以尝试使用If引导的条件句、虚拟语气等。
4. 注意连接词的灵活应用。例如表示转折的时候不要只用but,还可以用however, whereas, yet等。
5. 可以尝试使用从句结构，包括定语从句、状语从句等。如果担心从句的正确性，考生可以采用结构相对简单的从句。
6. 可以尝试使用并列句型，如on the one hand...on the other hand等结构。
7. 可以尝试使用插入语结构。即在长句中将主语和谓语动词分开，然后在中间插入修饰语。修饰语可以是分词结构，也可以是介词短语等。
8. 注意词汇的选择。尽量激发自己的思维，挖掘新鲜的词汇，不要只使用已经熟练掌握的高中词汇，要多尝试使用六级词汇。
9. 可以尝试使用数字和大写字母来为句子增色。
10. 针对不同的段落，句子的构成状况也可以进行相应的变化。例如文章的首段，尽量使用中等长度、结构和语法都不会出现错误的、把握性较大的句子。文章的主要部分，主题句要保证准确无误、通顺流畅。
下面我们为广大考生提供一些可以用在文章不同段落的有针对性的、较为经典的句型：
针对性句型
1. 我深信……： I am greatly convinced (that)从句/I am greatly assured (that)从句
【例】 我深信预防胜于治疗。=I am greatly convinced that prevention is better than cure. 2. ……是很容易证明的： It can be easily proved (that)从句
【例】 时间最珍贵是很容易证明的。=It can be easily proved that nothing is more precious than time。
3. ……无论如何强调都不为过： ...cannot be overemphasized
【例】 交通安全的重要性无论如何强调都不为过。=The importance of traffic safety cannot be overemphasized。
4. 在我看来……;我认为……: In my opinion.../To my mind.../As far as I am concerned.../I am of the opinion that从句
【例】 在我看来，打电子游戏既花费时间又有损健康。=In my opinion, playing video games not only takes much time but also is harmful to health。
5. 不用说……: It goes without saying that从句/Needless to say that从句/It is obvious that从句/Obviously,主语+谓语(+宾语)
【例】 不用说，早睡早起是值得的。=It goes without saying that it pays to keep early hours。
6. ……是不可能的;无法……: There is no+doing sth. /There is no way of+doing sth. /There is no possibility of+doing sth. /It is impossible to do sth. /It is out of the question to do sth. /No one can+do sth. /...cannot+do sth。
【例】 不可否认，事业成功的关键在于身心健康。=There is no denying that successful business lies in a healthy body and mind。
7. 人人知晓……/毫无疑问……： Everyone knows (that)从句/There is no doubt that从句
【例】 毫无疑问，近视在我国的年青人中是一个严重的问题。=There is no doubt that nearsightedness is a serious problem among the youth in our country。
8. ……是必要的： It is necessary that+主语 (+should)+谓语
……是重要的： It is important/essential+that 主语 (+should)+谓语
……是适当的： It is proper that+主语 (+should)+谓语
……是紧急的： It is urgent that+主语 (+should)+谓语
【例】 我们应当保持公共场所的清洁。=It is proper that we (should) keep the public places clean。
9. 据说……: It is said that从句
一般认为……： It is thought that从句
众所周知……： It is known that从句
据报道……： It is reported that从句
一般估计……： It is estimated that从句
【例】 众所周知，阅读增加我们的知识，开阔我们的心胸。=It is known that reading increases our knowledge and broadens our mind。
10. ……的主要原因是……: The main reason why...is that从句
【例】 青少年犯罪的主要原因是社会环境逐渐恶化。=The main reason why the juveniles commit crimes is that social environment is becoming worse。
经典句型
1. According to a recent survey, four million people die each year from diseases related to smoking.
根据最近的一项调查，每年有400万人死于与吸烟相关的疾病。
2. The latest surveys show that quite a few children have unpleasant associations with homework.
最近的调查显示相当多的孩子对家庭作业感到不满。
3. No invention has received more praise and abuse than Internet.
没有一项发明像互联网这样受到如此多的表扬和批评。
4. Many experts point out that physical exercise contributes directly to a person's physical fitness。
许多专家指出体育锻炼直接有利于身体健康。
5. In view of the seriousness of this problem, effective measures should be taken before things get worse.
考虑到问题的严重性，在事态进一步恶化之前必须采取有效的措施。
6. Proper measures must be taken to limit the number of foreign tourists and great efforts should be made to protect local environment from the harmful effects of international tourism.
应该采取适当的措施限制外国旅游者的数量，努力保护当地环境不受国际旅游业的不利影响。
7. Many city residents complain that there are so few buses in their city that they have to spend much more time waiting for a bus, which is usually crowded with a large number of passengers.
许多市民抱怨城市的公交车太少，以至于他们花很长时间等来的却是一辆已经载满乘客的公交车。
8. There is no denying the fact that air pollution is an extremely serious problem: the city authorities should take strong measures to deal with it.
不可否认，空气污染是一个极其严重的问题：市政部门应该采取有力措施来解决。
9. An investigation shows that women tend to have a favorable attitude toward retirement.
一项调查显示妇女对退休持赞成态度。
10. A proper part-time job does not occupy students' too much time. In fact, it is unhealthy for them to spend all of their time on study. As an old saying goes：“All work and no play makes Jack a dull boy。”
一份适当的兼职工作并不会占用学生太多的时间。事实上，把全部的时间都用到学习上并不利于学生的健康。俗话说得好：“只工作不玩耍，聪明孩子也变傻。”