This is the 418th most frequent Chinese word.
發展
"發展" means "development" or "to develop."
Here, '發展' is used as a verb to denote the growth and development of the city.
城市在最近幾年中快速發展。
The city has developed rapidly in recent years.
Here, '發展' again acts as a noun, describing the growth and expansion of the economy while implying an ongoing process.
經濟發展需要考慮環境保護。
Economic development needs to consider environmental protection.
In this case, '發展' functions as a noun referring to the progression and improvement of his career.