When I traveled briefly in Yunnan, down in Xishuangbanna, I frequently ran into folk where I, as a white foreigner with only 4 years of study under my belt, spoke Mandarin more fluently than they did - and this included people who were nominally Han, not one of the 50-odd ethnic minorities down there.

I'm not sure requirements can be said to be strict when the locals will tell you to your face that the mountains are high and the emperor far away.

> About 30 percent of China's 1.3 billion population, 400 million people, can't communicate in Mandarin