ageing phenomenon

例句：

1. 1.The elderly are often more susceptible to illnesses than younger people.
   老年人往往比年轻人更容易生病。
2. 2.As we age, our bodies undergo changes that affect our health and well-being.
   随着年龄的增长，我们的身体会发生变化，影响我们的健康和福祉。
3. 3.The ageing population is a major concern for many countries.
   老龄化的人口是许多国家的主要关切。