e.g. It was agreed by all of us that money should be raised for the project. ( unstressed ) 被动语态，应改为：All of us agreed that money should be raised for the project. ( stressed ) 主动语态。
(5)采用重复，句子中关键词或结构有时进行必要的重复，能起到对关键词或结构强调的效果，以加强句子的气势。
e.g. ① Government of the people， by the people， for the people shall not perish from the earth. (stressed) (Abraham Lincoln)
② Simplicity， simplicity， simplicity！ I say， let your affairs be as two or three， and not a hundred or a thousand .... Simplify， simplify. ( stressed ) ( Henry David Thoreau)以上两句都采用了重复，强调了关键词，增加了句子气势。
(6) 采用标点或符号，如分隔号、感叹号等。
e.g. ① The uncontrolled fire destroyed stores， offices， and houses. (unstressed)可以改为：The uncontrolledfire destroyed stores， offices， and houses. (stressed)或The fire was uncontrolled； it destroyed stores， offices， and houses. (stressed)或The fire was uncontrolled. It destroyed stores， offices， and houses. (stressed)第一种改法加分隔号，第二种加分号，第三种加句号，使句子强化The fire was uncontrolled。第三种强调效果最佳。
② When the bank robbers entered the bank they said， “Don"t move.” (unstressed)可以改为：When the bank robbers entered the bank they said， “Don"t move！”(stressed)把直接引语种的句号改为感叹号，效果就不一样。
(7) 采用强调词或句子结构，常用的强调词主要是副词或类似副词的词组、助动词等；结构有倒装句和it+be+被强调部分+ that（who）+原句剩余部分句式。
e.g. ①This is the very thing I have been looking for.
②Who on earth told you to do so？
③If you ever visit Beijing， you must go to see the Palace Museum.
④Nowhere else will you find so many happy， contented people.
⑤It was his life in the countryside that trained him into a strongminded， hardworking man.以上强调方式在中学一般作为语法讲述，在此只是简单一提。详细内容请看语法书。
以上概况的是句子的基本特征，也就是说，英语学习者在写句子时应该特别关注句子结构、用词及句子的有效构成。事实上，英语学习者在句子学习过程中往往会出现各种各样的错误。
二、句子常见错误分析
由于文化背景不同，导致语言表达习惯各异，在英语句子写作中，常出现一些用词、句法方面的错误或不足。为尽量避免出现这类现象，除多读英文原着外，写作时尽可能养成多推敲、修改和与他人交流的习惯。当然有针对性地训练也是必要和有效的。中国学生的英语句子错误总体可以分成代词指代不清、修饰语位置不对、句子成分残缺、串句和赘句五类。
1.代词指代，指代是否明确，有没有指代，直接关系句子的质量和读者的理解
e.g. 病句 (1) The teacher informed the student that he needed another test booklet. 句中的he 可能指the teacher，也可能是the student，指代含糊，影响理解。可改为：The teacher informed that the student needed another test booklet. 或改为：The teacher informed the student of giving him another test booklet.
病句 (2) In the armed services they can retire at an early age. 句中的they指谁，修饰语位置：The men and women in the armed services can retire at an early age.
2.修饰语位置，句中超过一个词可以被修饰语修饰，这时应注意修饰对象的明确和nearly， only， almost 的位置。
e.g. 病句 (1) The old man walked into the lamp post going to the optician. 可改为：While going to the optician， the old man bumped into the lamp post.
病句 (2) He almost ran twenty miles in the marathon race. 可改为：He ran almost twenty miles in the marathon race.
病句 (3) Students who study often get good grades. 可改为：Students who often study get good grades.
3.残缺句，是指缺少句子的某个成分
e.g. 病句 (1) Apparently the teacher did not notice that in the class was asleep.（缺主语）
可改为：Apparently the teacher did not notice that half the class were asleep.
病句 (2) Smith， who believes that it is good to help someone with “so little trouble to himself”.(成分多余)
可改为：Smith believes that it is good to help someone with “so little trouble to himself”.
病句 (3) After he finished the homework. He began watching TV. (应为两个连贯动作)可改为 ：After he finished the homework， he began watching TV.
4.串句，指的是两个以上的分句无标点符号或连词连接，或完全独立句子之间用逗号或错误连词连接
e.g. 病句 Students should be careful of punctuation of trouble will result if they are careless.句中无标点。可改为 (1) Students should be careful of punctuation. Trouble will result if they are careless. 或改为 (2) Students should be careful of punctuation， or trouble will result if they are careless. 或改为 (3) Students should be careful of punctuation； trouble will result if they are careless. 或改为(4) Students should be careful of punctuation， because trouble will result if they are careless.
5.赘句，是指用词过多，影响表达
e.g. 病句 In this modern world of today， we must get an education that will prepare us for a job in our vacation in life. 可改为：In the modern world， we must get an education that will prepare us for a job.在修改赘句时，主要从删除不必要的重复、用词代替词组，用词组代替句子等方面考虑。当表示相关意义的句子过多时，可采用调整句子的结构或删除不必要的结构或句子的方法，总之尽可能使句子简练。
（第五节）开头句和结尾句的写作
一、开头句
句子按其文中所处的位置可分为开头句、中间部分句和结尾句，要写好英语句子，根本在于多阅读、多写作，不存在哪些句子重要或不重要。但从考试的角度看，开头句和结尾句的写作就显得非常重要，也很难，为保证作文的得分，练习和熟记一些典型的句式是必要的，同时也是有效的。事实上考试的文体是相对固定的，因此很多句式是可以通过记忆练习，应考时更换部分关键词就可以完成表达。为此将基本句式粗略概述如下，供同学们训练：
e.g. (1) With the opening and reform policy being carried out， thousands upon thousands of ... are crowding into our country. They are eager to see this old mysterious land with a splendid culture of more than 5000 years.
作业：用英语表述该句：随着中国旅游业的发展，世界各地的人开始到中国各地旅游。他们渴望参观这个有着5000多年灿烂文化的神秘国家。
(2) There is a general discussion nowadays about the issue of .... Those who criticize... argue that.... They believe that.... But people who favor ...， on the other hand， maintain that....
作业：用英语表述该句：现在围绕官员腐败问题正在展开讨论。那些批评这种现象的人，认为官员腐败会导致政府腐败，从而认为必须尽快结束这种状况。
(3) When it comes to ... some people think that ... others claim that the opposite is true. There is probably some truth in both arguments， but ....
作业：用英语表述该句：当谈及计划生育问题时，一些人认为这是个好办法，另一些人则持不同的观点。双方皆有一定道理，而我认为计划生育是必要的。
(4) Today an increasing number of people have realized that...is of great importance. In order to ... every one of us is supposed to....
作业：用英语表述该句：现在越来越多的人意识到学好外语的重要性。为了找到好工作，很多人渴望最好掌握一门外语。
(5) When asked about ... the overwhelming majority of people think that .... But other people think that....
作业：用英语表述该句：当问起交通问题，大多数人抱怨交通拥挤，问题很严重。但别的一些人却不以为然。
(6) These days we often hear about .... They argue that.... But is it really so？ Close examination doesn"t bear out the claim.