Oh right, his lunar birthday is the 29th of the twelfth month. Because when he was a child, his birthdays were all organized by his grandfather, who only recognized the lunar calendar...
So in Qiao Yu's sixteenth year, he celebrated his birthday three times.
Another time he was called to Qingbei by his elder mentor, to see off Professor Zhang Shuwen, who he had only met once, back to the United States.
It was at this time that Qiao Yu learned that Professor Zhang was actually a professor and doctoral advisor at Princeton University. His role at Huaqing was merely as a visiting professor, and he would come to Huaqing once or twice a year to conduct some scheduled lectures and engage in some academic exchange activities at his elder mentor's mathematics research center.
