as的九大用法：
一)as作副詞，表示程度，意為“同樣地”。在“as...as...”，“not as...as...”結構中的第一個as是副詞，作“和/與...(不)一樣”解。eg：
Jack is as tall as his father.傑克和他的父親一樣高。
He doesn"t speak English as/so fluently as you.他的英語說得不如你流利。
二)as作介詞。
1.作“如，像”解。eg：
They got united as one man.他們團結得像一個人一樣。
2.作“充當，作為”解。eg：
As a writer，he was famous.作為作家，他是很有名的。
三)as作連詞，常用來連線主句和狀語從句。
1.引導時間狀語從句，作“當...的時候”解，有“隨著...”之意，與while意義相近，強調兩個動作同時發生;或某事一發生，另一事立即發生。eg：
He shouted aloud as her ran along.他一邊往前跑，一邊高聲地呼喊。
I was startled as he opened the door.他一開門，我嚇了一跳。
as作連詞，相當於when。eg;
As a little boy (When he was a little boy)he began to learn to play piano.他小時候就開始學彈鋼琴。
2.引導原因狀語從句，作“因為，由於”解，與because的用法相近。eg;
I must stop writing now，as I have rather a lot of work to do.我必須停筆了，因為我還有許多工作要做。
3.引導方式狀語從句或比較狀語從句，作“正如，(如)像”解。例eg：
As in your country，we grow wheat in the north and rice in the south.正如(像)你們國家一樣，我們在北方種小麥，在南方種大米。(方式狀語從句)
When at Rome，do as Romans do.入鄉隨俗。(方式狀語從句)
4.引導讓步狀語從句，作“雖然，儘管”解。這時從句常用倒裝語序，即把從句中的表語、狀語或動詞原形放在as之前。eg;
Strange as it may seem，it is true.儘管這事看上去很奇怪，但卻是真的。
Try as he might，Tom could not get out of the difficulties.不管怎樣努力，湯姆還是擺脫不了困境。
四)as作關係代詞。
1.引導限制性定語從句，用在“such...as”,“the same...as”，“as...as”等結構中，常譯作“像...一樣的人(或物)”，“凡是...的人(或物)”。例eg：
He wished to be such a man as Lei Feng was.他曾希望做一個像雷鋒那樣的人。
My hometown is no longer the same as it was.我的家鄉再也不像過去一樣了。
2.引導非限制性定語從句，用來指代它前面的整個句子(即先行句)，意思是“這一點”。這個分句可以位於句首、句中或句末。eg：
As is well known，oceans cover more than 70% of the earth.我們知道，海洋佔地球面積的百分之七十以上。
五)含as的固定片語的用法
1.as soon as作“一…就”解，引導時間狀語從句。eg：
As soon as I get to Beijing，I"ll write to you.我一到北京，就給你寫信。
2.as/so long as作“只要”解，eg;
As/So long as you study hard，you"ll make progress.只要你努力，你就會取得進步。
3.as if/though常用來引導方式狀語從句，作“好像，彷彿”解。如果從句中講的是非真實情況，則用虛擬語氣。eg：
She loves the child as if/though he were her own.她愛這個孩子如同愛自己的孩子。
As if/though也可用來引導表語從句，常用在“It appears/looks/seems...+as if/though”句型結構中。eg;
It appears as if/though it is going to clear up.看起來天要晴了。
It seems as if/though he knew nothing about it.他好像對此事一無所知。
4.as to作“關於，至於”解。eg;
There is no doubt as to his honesty.他的誠實是無可置疑的。
5.as much/many as作“多達...”，“達到...之多”解。eg：
He can earn as much as 5000 dollars a month.他每月能掙5000美元。
6.so/as far as I know作“就我所知”解，在句中作插入語。eg：
As/So far as I know，he will come here next Monday.據我所知，他將於下星期一到這裡來。
7.as a result，as a result of表示“由於...的結果”。eg：
She died as a direct result of the accident.她的死是那次事故的直接結果。
8，as well為“也，還”之意。eg：
Come early，and bring your brother as well.早點來，把你的弟弟也帶來。
9.so as to，so...as to若跟動詞原形，表示目的或結果。eg：
He studied hard so as to pass the exam.他努力學習以便透過考試。(表示目的)
as……as
AS +adj(原級)+AS
AS +adv(原級)+AS
as soon as 一……就
as soon as possible 儘可能快地
as early as possible 儘可能早的
as carefully as you can 儘可能認真地
as careful as you can 儘可能認真的
so...as 一般用於否定句,as...as 一般用於肯定句,(肯定否定都能用)
so...as不可用於肯定句.as...as與so...as均可表示"與……一樣",as...as...的用法:兩個as中間可以加形容詞或者副詞,由它要修飾的內容決定.
它們的用法有異同之處:
肯定句用as...as,不用so...as;否定句兩者均可使用.例如:
I didn"t go as /so far as you.我走得不像你那麼遠.
They walked as far as the station.他們步行到了車站.
誤:They walked so far as the station.
as的九大用法：
一)as作副詞，表示程度，意為“同樣地”。在“as...as...”，“not as...as...”結構中的第一個as是副詞，作“和/與...(不)一樣”解。eg：
Jack is as tall as his father.傑克和他的父親一樣高。
He doesn"t speak English as/so fluently as you.他的英語說得不如你流利。
二)as作介詞。
1.作“如，像”解。eg：
They got united as one man.他們團結得像一個人一樣。
2.作“充當，作為”解。eg：
As a writer，he was famous.作為作家，他是很有名的。
三)as作連詞，常用來連線主句和狀語從句。
1.引導時間狀語從句，作“當...的時候”解，有“隨著...”之意，與while意義相近，強調兩個動作同時發生;或某事一發生，另一事立即發生。eg：
He shouted aloud as her ran along.他一邊往前跑，一邊高聲地呼喊。
I was startled as he opened the door.他一開門，我嚇了一跳。
as作連詞，相當於when。eg;
As a little boy (When he was a little boy)he began to learn to play piano.他小時候就開始學彈鋼琴。
2.引導原因狀語從句，作“因為，由於”解，與because的用法相近。eg;
I must stop writing now，as I have rather a lot of work to do.我必須停筆了，因為我還有許多工作要做。
3.引導方式狀語從句或比較狀語從句，作“正如，(如)像”解。例eg：
As in your country，we grow wheat in the north and rice in the south.正如(像)你們國家一樣，我們在北方種小麥，在南方種大米。(方式狀語從句)
When at Rome，do as Romans do.入鄉隨俗。(方式狀語從句)
4.引導讓步狀語從句，作“雖然，儘管”解。這時從句常用倒裝語序，即把從句中的表語、狀語或動詞原形放在as之前。eg;
Strange as it may seem，it is true.儘管這事看上去很奇怪，但卻是真的。
Try as he might，Tom could not get out of the difficulties.不管怎樣努力，湯姆還是擺脫不了困境。
四)as作關係代詞。
1.引導限制性定語從句，用在“such...as”,“the same...as”，“as...as”等結構中，常譯作“像...一樣的人(或物)”，“凡是...的人(或物)”。例eg：
He wished to be such a man as Lei Feng was.他曾希望做一個像雷鋒那樣的人。
My hometown is no longer the same as it was.我的家鄉再也不像過去一樣了。
2.引導非限制性定語從句，用來指代它前面的整個句子(即先行句)，意思是“這一點”。這個分句可以位於句首、句中或句末。eg：
As is well known，oceans cover more than 70% of the earth.我們知道，海洋佔地球面積的百分之七十以上。
五)含as的固定片語的用法
1.as soon as作“一…就”解，引導時間狀語從句。eg：
As soon as I get to Beijing，I"ll write to you.我一到北京，就給你寫信。
2.as/so long as作“只要”解，eg;
As/So long as you study hard，you"ll make progress.只要你努力，你就會取得進步。
3.as if/though常用來引導方式狀語從句，作“好像，彷彿”解。如果從句中講的是非真實情況，則用虛擬語氣。eg：
She loves the child as if/though he were her own.她愛這個孩子如同愛自己的孩子。
As if/though也可用來引導表語從句，常用在“It appears/looks/seems...+as if/though”句型結構中。eg;
It appears as if/though it is going to clear up.看起來天要晴了。
It seems as if/though he knew nothing about it.他好像對此事一無所知。
4.as to作“關於，至於”解。eg;
There is no doubt as to his honesty.他的誠實是無可置疑的。
5.as much/many as作“多達...”，“達到...之多”解。eg：
He can earn as much as 5000 dollars a month.他每月能掙5000美元。
6.so/as far as I know作“就我所知”解，在句中作插入語。eg：
As/So far as I know，he will come here next Monday.據我所知，他將於下星期一到這裡來。
7.as a result，as a result of表示“由於...的結果”。eg：
She died as a direct result of the accident.她的死是那次事故的直接結果。
8，as well為“也，還”之意。eg：
Come early，and bring your brother as well.早點來，把你的弟弟也帶來。
9.so as to，so...as to若跟動詞原形，表示目的或結果。eg：
He studied hard so as to pass the exam.他努力學習以便透過考試。(表示目的)
as……as
AS +adj(原級)+AS
AS +adv(原級)+AS
as soon as 一……就
as soon as possible 儘可能快地
as early as possible 儘可能早的
as carefully as you can 儘可能認真地
as careful as you can 儘可能認真的
so...as 一般用於否定句,as...as 一般用於肯定句,(肯定否定都能用)
so...as不可用於肯定句.as...as與so...as均可表示"與……一樣",as...as...的用法:兩個as中間可以加形容詞或者副詞,由它要修飾的內容決定.
它們的用法有異同之處:
肯定句用as...as,不用so...as;否定句兩者均可使用.例如:
I didn"t go as /so far as you.我走得不像你那麼遠.
They walked as far as the station.他們步行到了車站.
誤:They walked so far as the station.