木有hints~
life expectancy unprecedented groundbreaking is are not carved in stone impractical unrealistic reflection nostalgic empty-nest syndrome midlife crisis confused bewildered puzzled disoriented mindset maturity dynamic linger in one's mind
life expectancy 人均寿命 unprecedented/ groundbreaking 史无前例的 is are not carved in stone 并非一成不变 impractical/unrealistic 不实际的 reflection 沉思 nostalgic 怀旧的 empty-nest syndrome 空巢综合症 midlife crisis中年危机 confused/bewildered/puzzled 困惑的 disoriented 迷失方向的 mindset 心态 maturity 成熟的 dynamic 有活力的 linger in one's mind 挥之不去