The trial of Socrates takes place in the year 399 and all of these refer to before the common era 399.

苏格拉底的审判,发生在公元前399年，这些,全都指向共同年代─399年之前。

耶鲁公开课 - 政治哲学导论课程节选

Malaria causes a million deaths per year, and schistosomiasis, which is a parasitic disease, is unfortunately a common cause of death in the world.

疟疾每年造成一百万死亡,而血吸虫病,这是一种寄生虫病,不幸的是,它是世界上很常见的死因

耶鲁公开课 - 生物医学工程探索课程节选