一、“There be”結(jié)構(gòu)
考生病句：
1、There are many people like to go to the movies.
2、There are different kinds of vegetables can be bought on the market by people.
正確表達：
1、There are many people who like to go to the movies.
2、There are different kinds of vegetables that people can buy on the market.
這兩個例句錯誤比較有普遍性，因為在歷次考試中有不少考生不能正確運用there be這一最常用句式。在這種結(jié)構(gòu)中，there是引導詞，沒有實際意義。be在句中作謂語，有時態(tài)和數(shù)變化。
例如：
1、There was no school in the village at that time. (there was not a school...)
注意：在否定句中，否定詞用no，也可用not a或not any。not a后接單數(shù)名詞，not a 后接復數(shù)名詞，no后面名詞單復數(shù)都可以。
2、There is not a moment to be lost.
3、There are many people rushing into the cities every year.
4、There are many things we can do to prevent traffic accidents.
5、There is no use holding back the wheel of history.
從以上例句還可看出，句中主語后面可接多種修飾語，如介詞短語、不定式短語、定語從句、分詞短語等等。這無疑使該結(jié)構(gòu)增加了表現(xiàn)力，使句子表達內(nèi)容更加豐富。 在運用這一結(jié)構(gòu)時，考生最容易犯錯誤是在there be之后又用了一個動詞作謂語，使句子結(jié)構(gòu)出現(xiàn)嚴重錯誤。這里列舉考生典型錯誤均屬這種情況，對此我們在寫作中要格外注意。

二、比較結(jié)構(gòu)
考生病句：
1、Comparing with the bike, the car runs much faster.
2、The climate in Walton is colder than other cities.
正確表達：
1、Compared with the bike, the car runs much faster.
2、The climate in Walton is colder than that of other cities.
評議與分析：許多考生在作文中用compare或than表示比較，但相當多表達有誤。
在例1中，對兩個事物進行比較句式為Compared with A, B...,只能用compare過去分詞，不能用現(xiàn)在分詞，因為B是分詞邏輯主語，只能被比較。在例2中，考生誤將“天氣”與“城市”進行比較，而二者沒有可比性，只有將后者改為“其他城市天氣”才符合邏輯，很顯然，考生錯誤是受了漢語表達習慣影響。比較結(jié)構(gòu)是常用結(jié)構(gòu)，正確地使用這一結(jié)構(gòu)可以使文章句式增加變化，有利于提高寫作成績。一般說來，考生若能恰當、正確地運用這一結(jié)構(gòu)，其寫作成績應在5分以上。
下面是比較結(jié)構(gòu)一些常用表達方法。
1、同級比較
1）、In 1998 we produced as many cars as we did in the previous five years.
2）、We have accomplished as much in the past three years as would have taken ten years in the past.

2、比較級
1）、Children now enjoy better medical treatment than before.
2）、We can live longer without food than we can (live ) without water.

3、最高級
1）、This is the most interesting book I've ever read.
2）、Of all his novels I like this one best.

4、the more…the more…結(jié)構(gòu)
1) 、The harder you work, the greater progress you will make.
2) 、The more a man knows, the more he discovers his ignorance.

5、選擇比較
1)、 I prefer staying at home to going out.
2) 、They prefer to work rather than (to) sit idly.
3) 、He prefers to work alone.
注意：這里1）句用是Prefer A to B結(jié)構(gòu)，to為介詞，后接名詞或動名詞；2）句是以不定式作prefer賓語；3）句用法同2），只是不把rather than部分表達出來。

6、對比
1)、 Motion is absolute while stagnation is relative.
2) 、He is tired out, whereas she is full of vigour.
注意：while 和whereas均可用于連接兩個意義對立分句，相當于漢語“而”字。許多考生能較好地運用這一句式，尤其在圖表作文中。
 

三、表達原因結(jié)構(gòu)
考生病句：
1、The real reason to our failure is not far to seek.
2、The reason for this is because some people want to earn plenty of money without
 working hard.
正確表達：
1、The real reason for our failure is not far to seek.
2、The reason for this is that some people want to earn plenty of money without working
hard.
評議與分析：
以上兩個病句分別引自92年1月和97年12月四級考試考生作文。從遣詞造句上看，這兩位考生具有一定寫作能力，not far to seek, plenty of money以及without working hard等均運用正確、恰當。但令人遺憾是，第一位考生不知道reason不與to搭配而應接介詞for，第二位考生犯了一個中國學生常犯錯誤，就是用because引起表語從句，because這個詞不能引起表語從句，在本句中只能改用that才正確。掌握好表達原因結(jié)構(gòu)是十分重要，幾乎所有寫作試題都要求寫原因或可以寫原因。在大學英語四、六級考試、研究生入學英語考試以及TOEFL考試中，寫作文體基本上是議論文，而議論文基本模式是擺事實、講道理，講道理就是說明原因。寫作測試文體決定了表達原因結(jié)構(gòu)重要性。
英語中用來表達原因這一概念結(jié)構(gòu)有多種。我們可用as , because, since, seeing that, considering that, now that, not that...等詞組引出表示原因從句。例如：
1、Now that we have seen these great achievements with our own eyes, we feel more
proud than ever of our country.
2、Professor Liu is strict with us because he wants us to make rapid progress.
3、Since we live near the sea, we enjoy a healthy climate.
4、Pollution is still a serious problem, not that we don't have the ability to solve it, but that
some people have not realized the consequences of the problem.
我們還可以借助某些詞語用簡單句表達原因結(jié)構(gòu)。例如：
1、The reason for this change is quite obvious.
2、Diligence is the key factor of success.
3、Idleness is the root of all evils.
4、He was ashamed to have made the mistake.(=He was ashamed that he had made the
mistake. =He was ashamed because he had made the mistake.)
除了上述例句外，英語中還有很多或易或難表達原因結(jié)構(gòu)。我們在進行寫作訓練時候，不能滿足于一知半解，要講究書面語言正確性和準確性。比如，because是最常用引導原因從句連詞，語氣最強，表示直接原因，若because置于句首，后面主句不能再用so。用as引導原因從句語氣較弱，所說明原因是附帶，而since表示原因暗示著是稍加分析之后才能推斷出來原因。
 

四、否定結(jié)構(gòu)
考生病句
1、Some people think we needn't to worry about fresh water.
2、Nowadays many people don't like to go to the movies, too.
正確表達：
1、Some people think we needn't worry (或don't need to worry) about fresh water.
2、Nowadays many people don't like to go to the movies, either.
評議與分析：
例句1選自96年1月四級考生作文，例句2選自92年1月六級考生作文。例句1 錯誤在于該考生混淆了need作為情態(tài)動詞和作為普通動詞用法。need作為情態(tài)動詞時，主要用于否定句，后面動詞不帶to, needn't worry，作we謂語。need作為實意動詞時，可用于肯定句、否定句和疑問句，don't need to worry 中to worry作don't need賓語。例句2錯誤在于該考生混淆了too和either區(qū)別，這兩個詞都表示“也”意思，但是在英語中too, also只能用于肯定句，而either只能用于否定句。