Walking to work is one way of improve air quality.
a. true
b. false

It is true that walking to work is one way of helping improve air quality. If you are walking, or riding a bicycle to your work, you are obviously not using a car or a bus which use fuel which pollutes air. So, if more people would do this, they would help improve their living conditions and the air we breathe, because each day, our air becomes more and more polluted.