A 73-year-old retired nurse spoke her native Tibetan all her life but never learned to write it — until now. Her decision offers a glimpse into how some embrace their language and cultural identity in Tibet, a region that is autonomous but tightly controlled by Beijing. China's new “ethnic unity” law mandates Mandarin as the primary language for schools and government. Critics argue the law forces assimilation and erodes the rights of Tibetans and other minorities. Beijing says the policies improve educational opportunities and ensure equal access for ethnic minorities. In Tibet, reminders of Chinese control are everywhere, from billboards to flags. Some Tibetans, like the retired nurse, are finding ways to preserve their language and culture amid the changes.