老化 (lǎo huà): (of a person, population or material) to age; (of knowledge) to become outdated

This refrigerator has been used for nearly twenty years, and its wiring is badly aged and often leaks electricity, so we had no choice but to replace it with a new one.

The elevator in the residential complex is aging, so it always makes a loud noise when running; the property management decided to thoroughly overhaul it next month.

Grandpa is getting older, and his skin ages quickly; even a slight bump easily causes bruises, so the family doesn't let him do heavy work.

Scientists have found that staying up late for a long time can accelerate brain aging and increase the risk of Alzheimer's disease, so they recommend that everyone maintain a regular sleep schedule.

The aging of urban infrastructure is a big problem; many water pipes have been used for fifty years and often burst, forcing the government to invest huge sums in renovation.