根据提供的文章，更改其中五个语法错误。
以下是一段关于篮球运动员的文章，其中有五个语法错误。
        Kobe Bryant was one of the more greater basketball players in NBA history. Not only he was a five-time NBA champion, but also he won two Olympic gold medals. He was known for his scoring ability and his fierce competitive nature. He retired in 2016 after a 20-year career.
以下是更正后的文章：
        Kobe Bryant was one of the greatest basketball players in NBA history. Not only was he a five-time NBA champion, but he also won two Olympic gold medals. He was known for his scoring ability and his fierce competitive nature. He retired in 2016 after a 20-year career.