听下面一段材料，回答第1、2、3题。 1. What could old people do if they wanted to stay young? [     ] A. Think well of their old ages. B. Go back to college. C. Get attention paid to their brain. 2. Which of the following statements is not true? [     ] A. The retired electrical engineer can't earn much money now. B. The housewife is now a famous industrial designer. C. The 71-year-old man later became a lawyer. 3. Which of the following expresses the main idea of the passage? [     ] A. It is never too old to learn. B. You can keep yourself young if you care enough to try. C. Keeping an active mind is an easy thing.