－Which city is your favorite?－Hangzhou, of course. It is the _____ place that I have ever visited.

-What do you think of the traffic in our city?-lt's    than it used to be, but there's still a long way to go.

---If there are ______ people driving , there will be ______ air pollution.--- Yes, the air will be fresher.

— How clever you are! How can I know as much as you?— ______ you read, _______ you can learn.

If there are ____trees, the air in our city will be ____cleaner.