Li Yan, an engineer, was born on February 9, 1965 in Beijing, China. After he graduated from Qinghua University in 1987,

Li Yan, an engineer, was born on February 9, 1965 in Beijing, China. After he grad【爱英语 爱生活 爱上英语翻译学习网（enfanyi.com）分享时尚英语资