问题补充：
The average temperature this year is that of last year.
A. as not high as
B. not as high
C. not as higher as
D. not as high as
答案：
A. as not high as
B. not as high
C. not as higher as
(答案→)D. not as high as
解析：as...as用法：
as...as意为和……一样，表示同级的比较。使用时要注意第一个as为副词，第二个as为连词。其基本结构为：as+ adj./ adv. +as。
其否定式为not as/so +adj./ adv. +as。
故选D.
