The air in Lanzhou is getting much _____ now than a few years ago .
The traffic light is yellow, you may __________. A. stop B. wait C. go
They like __________ to music. A. listening B. listens C. listen
Lucy is ten. Kate is nine years old. So Lucy is __________ than Kate. A. older B. younger C. fatter
-Whose ruler is it? -Maybe it's____。 A. Peter B. Peters C. Peter's
I'v got a toothache. I'm going to the____. A. park B. dentist C. teacher