Ten years ago, there were many narrow streets.But now many streets have been widened. So buses and cars can go more quickly than before.  Ten years ago  ,  it was not convenient to go from the north of the city to the south.  But now, you are sure to reach anywhere in less than an hour. To our joy, we have two underground lines and many more are being built. We seldom find traffic jam in rush hours. So we don't have to worry about going out. With the development of science and technology, the transportation in Shanghai will become all the better.