The subway has become the preferred means of travel for many big city residents. It is fast and there is absolutely no worry about traffic jams; it is safe and there will be no traffic accidents in the subway; and it is cheap and is only slightly more expensive than bus fares.
I am a person who has a special habit of taking the subway. I like to stare out of the subway window. Every time I take the subway, watching the subway leave the station and enter the dark tunnel, I always feel like I am being swallowed up in my heart.
Will there be a day when the subway will no longer be able to get out?
Or it came out but one carriage was missing?
In the dark tunnel, God knows what will happen?