keep-fit的用法和样例：
例句
用作名词 (n.)
- Gymnasts do everyday exercises to keep themselves limber.
体操运动员每天都做运动保持身体柔软。 - The pain of the coughing fit had not quite driven out of Winston's mind the impression made by his dream, and the rhythmic movements of the exercise restored it somewhat.
那场大梦在温斯顿心里留下的痕迹煞是强烈，咳嗽大发作带来的痛苦也未能赶它出去，体操有节奏的动作倒有点恢复了它。
