But over time, society is more and more competitive. Everything is fast making the man must have invented new technologies. The bike has become something that cannot meet the requirements of a good man. Humans need to devise a new vehicle so that it is more convenient, fast, to serve the needs of human beings, because of the bicycle requires the capability and physical strength of the body in cycling. This makes the bike could not make man to travel quickly and easily if excessive cycling may cause bodily injury.
การแปล กรุณารอสักครู่..