Last week I visited one of my old neighborhoods in Washington D. C. I hadn't been there for twenty years and as I walked along the street, my mind was flooded by memories of the past. I saw the old apartment building where I had lived and the playground where I had played. As I viewed these once familiar surroundings, images of myself as a child there came to mind. However, what I saw and what I remembered were not the same. I sadly realized that the best memories are those left untouched. My old apartment building, as I remember, was bright and alive. It was more than just a place to live. It was a movie house, a space station, or whatever my young mind could imagine. I would steal away with my friends and play in the basement. This was always exciting because it was so cool and dark, and there were so many things there to hide among. There was a small river in the back of the building. We would go there to lie in the shade of trees and enjoy ourselves. However, what I saw was completely different. The apartment building was now in disrepair. What was once more than a place to live looked hardly worth living in. The windows were all broken. The once clean walls were covered with dirty marks. The river was hardly recognizable. The water was polluted and the trees and flowers were all dead. The once sweet smelling river now smelled terrible. It was really heartbreaking to see all this. I do not regret having seen my old neighborhood. However, I do not think my innocent child hood memories can ever be the same. I suppose it is true when they say,' You can never go home again.' In the first two paragraphs of the passage, the writer tries to tell us that ______.