as+形容詞或副詞原級+as 意為“同……一樣”,表示同等比較,它的否定式可有兩種形式:
不如……
not so...as
not as...as
This box is as big as that one. 這個盒子同那個盒子一樣大 。
This box is not so big as that one. 這個盒子不如那個盒子大 。
She sings as well as Mary. (正)她唱得同瑪麗一樣好 。
She doesn't sing as well as Mary. (正)她唱得不如瑪麗好 。
She sings as better as Mary. (誤)
She sings not as well as Mary. (誤) (應否定謂語 )