a retired doctor的用法和样例：
- In the 1990s, Gao, a retired doctor, exposed a government-supported, blood buying program that led to the spread of HIV, the virus that causes AIDS, among thousands of poor farmers in the province.
- The retired doctor found a refuge in music.
- I put him down as a retired naval officer.
- Noticing his military beating, I put him down as a retired major.
- He is now living in a retired spot.