Some people like to play with their cell phones while waiting for the bus. But people in Shenzhen might miss their bus if they don’t pay attention. Shenzhen now has 16,000 electric (电动的) buses. It is the world’s first fully electric bus fleet (纯电动公交车队). The buses are very quiet, since they run on electricity. The loudest sound they make is the “beep beep” of their doors opening. They are also good to the environment (环境).