The air in Lanzhou is getting much now than a few years ago .A. cleanB. cleanerC. cleanes

问题补充：

The air in Lanzhou is getting much now than a few years ago .

A. clean

B. cleaner

C. cleanest

D. the cleanest

答案：

A. clean

(答案→)B. cleaner

C. cleanest

D. the cleanest

解析：此题重点考察形容词或副词的比较级的特殊用法，其前可以用much，even等词来修饰。