To begin, year to year world is developing , so number of big cities are growing. Is it made a new problems? Firstly, if area of cities will be larger, statistics of unemploment will grow. This problem actually even now. To solve this problem goverments should give more opportunities for people , who haven't got a job. Another solution is that here will be social problems. For this reason here some examples like traffic jams, noisy and polluted streets. People can participete on volonteering to resolve it. Foretheremore, It can be catalyzer to start using alternative energy. All in all , in my opinion, it is bad idea . I get used to my city and streets, i think all like there childhood places and don't want to change