navigational mark的用法和樣例：
例句
- Of course, he must obey the race rules and try to avoid committing such fouls as hitting the yachting mark.
當然要遵守比賽規則，盡量避免像碰撞航標之類的犯規。 - Urban dominant industry is an important underpinning of regional economic development, and is a navigation mark of regional industry modernization.
摘要區城城市主導產業是區城經濟發展的主要支柱，是區域產業現代化的航標。
