1）在否定句或疑问句中可用so… as。　　　He cannot run so/as fast as you.2）当as… as 中间有名词时采用以下格式。　　　 as +形容词+ a +单数名词　　

1）在否定句或疑问句中可用so…as。
Hecannotr unso/asfastasyou.2）当as…as中间有名词时采用以下格式。
as+形容词+a+单数名词
as+many/much+名词
Thisisasgoodanexampleastheotheris.
Icancarryasmuchpaperasyoucan..3）用表示倍数的词或其他程度副词做修饰语时，放在as的前面。
Thisroomistwiceasbigasthatone.
Yourroomisthesamesizeasmine. 4)倍数+as+adj.+as <=>倍数+then+of
Thisbridgeisthreetimesaslongasthatone.
Thisbridgeisthreetimesthelengthofthatone.
Yourroomistwiceaslargeasmine.
Yourroomistwicethesizeofmine.