It is a fine Saturday morning. Lily and Lucy get up at six thirty. They want to go to the Great Wall  with their mother. At seven fifty they are in a big bus to the Great Wall. There are forty people in it. Some of them are Americans, some are English. There are two Chinese in the bus, too. One is a woman. She is driving the bus. The other is a young man. He's now talking about the Great Wall in English. They are listening to him. At about nine o'clock, they get to the Great Wall. The young Chinese man is   _  .
driving the bus talking to the people listening to him doing nothing