剑桥词典the period of your life , usually considered to be from about 45 to 60 years old , when you are no longer young , but are not yet old 中年（通常指45岁至60岁之间） Once you reach middle age , you have to be sensible about your health . 一旦步入中年，你必须明智地对待自己的健康。 返回 middle age