Write a paragraph by rearranging the following sentences in correct sequence. (The first and the last sentences are already in order.)
- The city was full of refugees - without food and shelter.
- A passerby took pity on the old man.
- The old man used only the copper coin to buy some noodles for his grandson.
- He dropped a silver and a copper coin into the old man's apron.
- A vendor was selling noodles nearby.
- He kept the silver coin to buy seeds.