Given a time machine or a Time Turner, I would tell my 21-year-old self that personal happiness lies in knowing that life is not a check-list of acquisition or achievement.

• 假如有一台时间机器或者一条时光隧道，我会告诉21岁时的自己，人生的幸福依傍于这样的觉悟：生活不是一张成就或者功绩的核对表。