a sister city affiliation的用法和样例：
- Crespina, with about four thousand people, became a sister city to Staten Island.And Tuscan winemaker Piergiorgio Castellani became a technical adviser to the project.
- An express train traveling from eastern India's Howrah, a sister city of Calcutta, to the capital New Delhi derailed on a bridge over Dhabi River in the state of Bihar on the 9th at 10:40 PM local time.
- It's for a delegation from our sister city in Germany.
- I have two brothers and a sister: three siblings in all.
- She has a sister much younger than she is.