A、The doctor was very rich. B、The doctor knew him well. C、The doctor used the chance to thank him for his advice. D、The doctor w

Ought you to give other people advice how to live their lives? I don’t know. But sometimes it is possible to give good advice.
    When I was young, a stranger came to my house; a small man with shabby clothes and a round red face. He told me he was working in a small hospital but didn’ t like his job there. He asked whether there would be any opportunities for an English doctor in Spain. I warned him that Spain was not always the Spain of grand opera, but that he might earn enough to keep body and soul together. He must decide for himself.
    He left me and I soon forgot him. Some years later I happened to be in Valencia. Feeling rather unwell, I asked the hotel porter if there was an English-speaking doctor in the town. He gave me an address.
    When I reached the house, a small cheerful-looking man met me. He was the English-speaking doctor and invited me in. After he had examined me and told me what to do, I asked what his fee was.
    He shook his head. "There’ s no fee. Don’t you recognize me? I was wondering whether I’d ever have a chance of thanking you for what you’ ve done. You told me I’ d earn enough money to keep body and soul together and I haven’ t done much more than that. I shall never be rich, but that doesn’ t matter at all. I’ m happy, I enjoy my job, and I wouldn’ t exchange it for anything else in the world. "
21. What does the speaker think it to give other people advice about how to live their lives?
22. What did the stranger who once visited the speaker’ s house ask?
23. What’ s the speaker’ s answer toward the stranger’ s question?
24. Why didn’t the doctor charge the speaker?
25. Where did the speaker see the stranger again?