How to build a greener cityAs we know,Yiwu is an international city. It attracts more and more people to come and do business.So it's our ty to build a beautiful green city. As students,we shouldn't throw rubbish anywhere on the ground or use too many plastic bags. Ask the factories not to put waste water into the river and we'd better not go to school by car so that we can rece the air pollution. What's more, we should plant more trees and flowers to make our city greener. Let's work hard for our city tohave a good environment.