1) Are there numerous escalators which help to keep the traffic moving?
2)Was safety always one of the main cocerns of london transport?
3) What is the longest continuous railway tunnels in the world?
4)Automatic signalling is operating by the trains themselves, isn't it?
5)Is the crime level in the Underground rather high ?
6) Is the air in the Underground changed every quarter of an hour?
7) Is the underground becoming much cleaner and brighter?