例：As(it is)in your country, we grow wheat in the north and rice in the south.
(2) as+形容词/副词原级+(a /an)+名词+as ;
否定式：not as/so --- as
例：He is as good a player as his sister.
(3) such + n. + as to do 如此……以致于……
例：She is such a fool as to believe what he said.
(4) so + adj./adv. + as to do sth 如此……以致于……
例：He was so strong as to carry the heavy box.
(5) such...as... 象……之类的…… (接名词或定语从句)
例：He wished to be such a man as Lei Feng was.
(6) the same +名词+as 和……一样的…… (接名词或定语从句)
例：He is not the same man as he used to be.
(7) as 引导非限制性定语从句
例：As is known to us, knowledge is power.
例：We get wiser as we get older.
(9) 引导原因状语从句，与 because的用法相近
例：As it was getting very late, we soon turned back.
例：Child as he is, he knows much about science.
2 prefer 句型
(1) prefer to do sth
例：I prefer to stay at home.
(2) prefer doing sth
例：I prefer playing in defence.
(3) prefer sb to do sth
例：Would you prefer me to stay?
(4) prefer to do sth rather than do sth ……
例句：I prefer to stay at home rather than go out.
(5) prefer doing sth to doing sth
例：I prefer watching football to playing it.
(6) prefer sth to sth
例：I prefer tea to coffee.
(1) be doing sth...when...
例：He was still smiling when the door opened and his wife came in.
(2) be about to do sth ... when ...
例：We were about to start when it began to rain.
(3) had just done ... when ...
例：I had just gone to bed after a very hard day when the phone rang.
(1) It +seems + that从句
例：It seemed that everyone was satisfied.
(2) It seems to sb that ...
例：It seems to me that she is right.
(3) There seems to be ...
例：There seems to be a heavy rain.
(4) It seems as if ...
例：It seemed that she couldn't come to class.
(1) She is taller than I by three inches.
(2) There is one year between us.
(3) She is three years old than I.
(4) They have increased the price by 50%.
(5) His salary has rised to 10,000 yuan per month.