in hanghai, therere mainly four mean of tranportation,the underground, tai, bue and electric bike. the underground i much fater than tai and bue. bue are the cheapet but the lowet of the four. tai run more quickly than bue, but they are more epenive. now, more and more people chooe to ue electric bike. the electric bike i both clean and mobile. it alo ave money. it i the mot convenient mean of tranportation.