人性: human nature, humanity, human, the totality of human attributes...
觉得: to think, to feel...
改善: to make better, to improve...
手工: handwork, manual...
周转: to rotate, to circulate (cash, stock etc), turnover, circulation, cash flow...
外公: (coll.) mother's father, maternal grandfather...
铅: lead (chemistry)...
微博: microblogging, microblog...
帝国: empire, imperial...
概念: concept, idea...