so

as

to引导的结构只能放在句子后面，且通常用于否定结构中，如:he

arrived

here

very

early

so

as

not

to

miss

the

chance

to

meet

his

friend.

so

that是如此,以至于的意思，常用于句中

as…as是和什么一样的意思，a

is

as

well

as

b

，意思是a

和b

一样好的意思