I.单项选择(15分)1.Moreandmorepeoplehavealow-carbonlifeandtheairisgettingmuchthanbefore.A.cleanB.cleanestC.cleanerD.thecleanest
I.单项选择(15分)
1. More and more people have a low-carbon life and the air is getting much than before.
A. clean B. cleanest
C. cleaner D. the cleanest
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