One day, Mr Smith is going to take a train to his hometown. When the train starts, one of his shoes falls to the ground. The train is going faster and faster, and he can't pick it up. Then he quickly takes off the other shoe and throw it on the ground near the fallen  shoe. A little boy on the train asks him, "Why do you do that? You have lost  one shoe. "Mr Smith answers, " If a man picks them up, he may get a pair of shoes. " Mr Smith is going to his hometown  _  .
by bus by train by bike on foot