Complex sentence: These national holidays were first started by the government for PRC's National Day in 1999 and are primarily intended to help expand the domestic tourism market and improve the national standard of living, as well as allowing people to make long-distance family visits.
Split into simpler sentences: These national holidays were first started by the government for PRC's National Day in 1999. They are primarily intended to help expand the domestic tourism market and improve the national standard of living, as well as allowing people to make long-distance family visits.