Post Essay It's a good idea to prepare your essay in a word processor and paste [Ctrl+V] it here. Please save a copy for your own record before submitting. Topic 1249 - One way to solve the problem of congestion in cities is to build sky trains which run overhead rather than on or under the ground. What are the advantages and disadvantages of using this solution to solve congestion? Post Title Your Name Your Email 2 + 8 = Post Content Human verification: leave this field empty.