By 2050，nearly （将近） 70% of the world's population （人口） will live in cities. Many of them will become large cities with a population of more than 10 million. Moving people around each large city will be difficult. The traffic speed （速度） in London will fall to about 7 miles （英里） per （每） hour. Around the same speed （速度） it was 150 years ago，in the days of the horse and cart. But city planners are working on ways to solve （解决） the problem.
Self﹣driving cars
Robot taxis | Self﹣driving cars （无人驾驶汽车） or robot taxis will play a part. There'll be more than 30 million self﹣driving cars on the road by 2040. People don't need to drive by themselves. By 2050，there will be robot taxis in the city streets. We can call the taxis very quickly. |
| Public transport （公共交通工具） like buses will be highly personalized （个性化）. People don't need to look through the bus timetable. Buses will be connected on the Internet and make the way by themselves according to （根据） where the people need to go. |
| Bikes will be helpful and safe，too. Cities could build special roads for them high above city streets. Xiamen in southeast China already has an 8﹣kilometer bicycle way to protect riders like that. That may be another kind of transport in 2050. It will be wonderful. |
Buses
Bikes
