As medical services and scientific technologies advance, people’s average life expectancy has been greatly increasing, and population ageing has become a global phenomenon
As medical services and scientific technologies advance, people's average life expectancy has been greatly increasing, and population ageing has become a global phenomenon
As medical services and scienti fi c technologies advance, people's average life expectancy has been greatly increasing, and population ageing has become a global phenomenon.
As medical services and scienti fi C technologies advance people ', s average life expectancy has been, greatly increasing and. Population ageing has become a global phenomenon.