大學英語四級作文怎樣才能寫好
一、 ＂There be＂結構 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：
e are many people who like to go to the movies.
2. There are different kinds of vegetables that people can buy on the market.
這兩個例句的錯誤比較有普遍性，因為在歷次考試中有不少考生不能正確運用there be這一最常用的句式。在這種結構中，there是引導詞，沒有實際意義。be在句中作謂語，有時態和數的變化。例如：
1. There was no school in the village at that time. 注意：在否定句中，否定詞用no，也可用not a或not any。not a後接單數名詞，not many後接複數名詞，no後面的名詞單複數都可以。
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，句中的主語後面可接多種修飾語，如介詞短語、不定式短語、定語從句、分詞短語等等。這無疑使該結構增加了表現力，使句子表達內容更加豐富。 在運用這一結構時，考生最容易犯的錯誤是在there be之後又用了一個動詞作謂語，使句子結構出現嚴重錯誤。這裏列舉的考生的典型錯誤均屬這種情況，對此我們在寫作中要格外注意。
二、 比較結構
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，但相當多的表達有誤。 在例1中，對兩個事物進行比較的句式為Compared with A, B...,只能用compare的過去分詞，不能用現在分詞，因為B是分詞的邏輯主語，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，只有將後者改為 其他城市的天氣 才符合邏輯，很顯然，考生的錯誤是受了漢語表達習慣的影響。
比較結構是常用結構，正確地使用這一結構可以使文章的句式增加變化，有利於提高寫作成績。一般説來，考生若能恰當、正確地運用這一結構，其寫作成績應在5分以上。
下面是比較結構的一些常用的表達方法。
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 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 結構
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 sit idly. 3) He prefers to work alone.
注意：這裏的1）句用的是Prefer A to B結構，to為介詞，後接名詞或動名詞；2）句是以不定式作prefer的賓語；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 vigor.
注意：while 和whereas均可用於連接兩個意義對立的分句，相當於漢語的 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、 表達原因的結構
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：
從遣詞造句上看，這兩位考生具有一定的寫作能力，not far to seek, plenty of money以及without working hard等均運用正確、恰當。但令人遺憾的是，第一位考生不知道reason不與to搭配而應接介詞for，第二位考生犯了一箇中國學生常犯的錯誤，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。掌握好表達原因的結構是十分重要的，幾乎所有的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，寫作的文體基本上是議論文，而議論文的基本模式是擺事實、講道理，講道理就是説明原因。寫作測試的文體決定了表達原因結構的重要性。
英語中用來表達原因這一概念的結構有多種。我們可用as , because, since, seeing that, considering that, now that, not that...等詞組引出表示原因的從句。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.
我們還可以藉助某些詞語用簡單句表達原因結構。例如：
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.
除了上述的例句外，英語中還有很多或易或難的表達原因的結構。我們在進行寫作訓練的時候，不能滿足於一知半解，要講究書面語言的正確性和準確性。比如，because是最常用的引導原因從句的連詞，語氣最強，表示直接的原因，若because置於句首，後面的主句不能再用so。用as引導的原因從句語氣較弱，所説明的原因是附帶的，而since表示的原因暗示着是稍加分析之後才能推斷出來的原因。
四、 否定結構
考生病句
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 about fresh water.
2. Nowadays many people don＇t like to go to the movies, either.
評議與分析：
例句1 的錯誤在於該考生混淆了need作為情態動詞和作為普通動詞的用法。need作為情態動詞時，主要用於否定句，後面的動詞不帶to, needn＇t worry，作we的謂語。need作為實意動詞時，可用於肯定句、否定句和疑問句，don＇t need to worry 中的to worry作don＇t need的賓語。
例句2的錯誤在於該考生混淆了too和either的區別，這兩個詞都表示 也 的意思，但是在英語中too, also只能用於肯定句，而either只能用於否定句。
否定結構除了在助動詞、情態動詞，be和have後面加not之外，還有許多不含not的否定結構。
I. 含有否定意義的詞彙和短語 以下列舉的詞和詞組本身就具有否定的含義，因此無需用否定詞。介詞against, beyond, but, except, without,...形容詞和動詞absent, deny, differ, different, fail, free, ignore, miss, refuse, the last, used to, reluctant, lack, want,...短語, , , let alone, at a loss, in vain, instead of, out of the question, rather than, , by no means, anything but,... 例句：
1） Women fail to get the equal rights in some countries.
在一些國家裏婦女沒有得到平等的權利。
2） This is by no means the best way to solve the problem of energy crisis.
這不是解決能源危機的最好的辦法。
3） We should protect trees from being destroyed.
我們應保護樹木，不讓它們受破壞。
4） In old China we could not make a nail, let alone machines.
在舊中國，我們連一個釘子都造不了，更不用説製造機器了。
II. 含有半否定意義的詞語barely, hardly, few, little, rarely, scarcely, seldom, not all, not everyone, not everything,...具有半否定的意義。例句：
1） We could hardly see any fresh vegetables in winter on market several years ago.
幾年前在冬天市場上很難見到新鮮蔬菜。
2） These young people know little about how to choose good books to read.
這些年輕人幾乎不知道如何挑選優秀的書籍來讀。
III. 不含否定意義的否定結構有些詞和詞組形式上是否定結構，但其含義是肯定的，比如：cannot but, can＇t help, no , l, in no time, none other than, nothing but,等等。例句：
1） We can＇t but face the reality. 我們只有面對現實。
2） These old buildings will be replaced by modern apartment buildings in no time.
這些舊建築將很快為現代化的公寓所代替。
IN. 否定結構的倒裝語序. 我們有時為了強調而把否定詞和詞組放在句首，這時句子結構應倒裝。例如：
1） On no account should we follow blindly.我們決不應當盲從。
2） No where has the world ever seen such great enthusiasm for learning as in our country.沒有任何其他地方有我國這樣高的學習熱情。
五、 含有it的結構
考生病句：
1. As is known to all of us that science and technology play an important role in the development of society.
2. It is known to us, practice makes perfect.
正確表達：
1. It is known to all of us that science and technology play an important role in the development of society.
2. It is known to us that practice makes perfect.
評議與分析：
很顯然，兩個考生混淆了it和as的用法。如果用it作形式主語，後面的主語從句必須由that引起；如果用as，則後面不能用that，因為as是關係代詞，代表practice makes perfect。It 在英語中是個相當活躍的代詞，在寫作中我們常要使用它。以下幾種用法應熟練掌握，並能靈活運用。
1．作形式主語
It is necessary for us to master a foreign language skillfully. It makes difference whether we could purify the air or not.
2.作形式賓語
We find it rather difficult to prevent people from doing that. Modern science has made it possible for babies to gro
w healthily and for people to live longer.
3.引導強調句
It is only by this way that we can achieve success. It was then that people began to realize the importance of controlling population.
從語法結構來看，上述的句子都不難，或者可以説是考生相當熟悉的。然而在寫作考試中，多數考生缺乏運用自己已掌握的句式的意識，而以自己頭腦中拼湊的中式英語取而代之。其實，只要能恰當地運用上述的任何一個句式，考生的作文就會出現閃光點，就會取得比較好的'成績。
英語寫作常見錯誤與分析
下面我們對一些在英語寫作中典型的病句實例逐一加以剖析．
一． 不一致（Disagreements）
所謂不一致不光指主謂不一致，它還包括了數的不一致, 時態不一致及代詞不一致等．
病句： When one have money, he can do what he want to.
剖析：one是單數第三人稱，因而本句的have應改為has ;同理，want應改為wants.本句是典型的主謂不一致．
改為： Once one has money, he can do what he wants
二． 修飾語錯位（Misplaced Modifiers）
英語與漢語不同，同一個修飾語置於句子不同的位置，句子的含義可能引起變化．對於這一點中國學生往往沒有引起足夠的重視，因而造成了不必要的誤解．
病句：I believe I can do it well and I will better know the world outside the campus.
剖析：better位置不當，應置於句末．
三． 句子不完整（Sentence Fragments）
在口語中，交際雙方可藉助手勢語氣上下文等，不完整的句子完全可以被理解．可是書面語就不同了，句子結構不完整會令意思表達不清，這種情況常常發生在主句寫完以後，筆者又想加些補充説明時發生．
病句：There are many ways to know the society. For example by TV ,radio ,newspaper and so on .
剖析：本句後半部分＂for example by TV ,radio ,newspaper and so on . 不是一個完整的句子，僅為一些不連貫的詞語，不能獨立成句．
改為：There are many ways to know society ,for example ,by TV ,radio ,and newspaper.
四． 懸垂修飾語（Dangling Modifiers）
所謂懸垂修飾語是指句首的短語與後面句子的邏輯關係混亂不清．
病句： At the age of ten, my grandfather died.
這句中＂at the age of ten＂只點出十歲時，但沒有説明 誰 十歲時．按一般推理不可能是my grandfather, 如果我們把這個懸垂修飾語改明確一點，全句就不那麼費解了．
改為：When I was ten, my grandfather died.
病句:To do well in college, good grades are essential.
剖析：句中不定式短語 to do well in college 的邏輯主語不清楚．
改為：To do well in college, a student needs good grades.
五． 詞性誤用
詞性誤用 常表現為：介詞當動詞用；形容詞當副詞用；名詞當動詞用等．
病句：None can negative the importance of money.
剖析：negative 系形容詞，誤作動詞。
改為：None can deny the importance of money.
六． 指代不清
指代不清主要講的是代詞與被指代的人或物關係不清，或者先後所用的代詞不一致。 Mary was friendly to my sister because she wanted her to be her bridesmaid.
讀完上面這一句話，讀者無法明確地判斷兩位姑娘中誰將結婚，誰將當伴娘。如果我們把易於引起誤解的代詞的所指對象加以明確，意思就一目瞭然了。這個句子可改為：
Mary was friendly to my sister because she wanted my sister to be her bridesmaid.
And we can also know the society by serving it yourself.
剖析：句中人稱代詞we 和反身代詞yourself指代不一致。
改為：We can also know society by serving it ourselves.
七． 不間斷句子
什麼叫run-on sentence? 請看下面的例句。
病句: There are many ways we get to know the outside world.
剖析：這個句子包含了兩層完整的意思： There are many ways. 以及 We get to know the outside world. 。簡單地把它們連在一起就不妥當了。
改為：There are many ways for us to learn about the outside world. 或：
There are many ways through which we can become acquainted with the outside world
八． 措詞毛病
Diction 是指在特定的句子中如何適當地選用詞語的問題，囿於教學時間緊迫，教師平時在這方面花的時間往往極其有限，影響了學生在寫作中沒有養成良好的推敲，斟酌的習慣。他們往往隨心所欲，拿來就用。所以作文中用詞不當的錯誤比比皆是。
病句：The increasing use of chemical obstacles in agriculture also makes pollution.
剖析：顯然，考生把obstacles 障礙 ， 障礙物 誤作substance 物質 了。另外 the increasing use 應改為 abusive use 。
改為：The abusive use of chemical substances in agriculture also causes/leads to pollution.
九． 累贅
病句：In spite of the fact that he is lazy, I like him.
本句的 the fact that he is lazy 系同謂語從句，我們按照上述 能用詞組的不用從句 可以改為：In spite of his laziness, I like him.
病句： For the people who are diligent and kind, money is just the thing to be used to buy the thing they need.
剖析：整個句子可以大大簡化。
改為：Diligent, caring people use money only to buy what they need.
十． 不連貫
不連貫是指一個句子前言不對後語，或是結構上不暢通。這也是考生常犯的毛病。
病句： The fresh water, it is the most important things of the earth.
剖析：The fresh water 與逗號後的it 不連貫。It 與things 在數方面不一致。
改為：Fresh water is the most important thing in the world.
