role作用可数吗

　　Prevention also plays a central role in traditional medicine.

　　预防在传统医学中也起着主导作用。

　　Money played an important role in his life.

　　金钱在他的生活中扮演了重要的角色。

　　He's a natural for the role.

　　他是这个角色的最佳人选。

　　She was offered the leading role in the new TV series.

　　她获得主演那部新的电视连续剧的机会。