Qiē / ěr / nuò / bèi / lì / hé / shì / gù / shì / rén / lèi / lì / shǐ / shàng / zuì / yán / zhòng / de / hé / zāi / nàn / zhī / yī / 。切尔诺贝利核事故是人类历史上最严重的核灾难之一。The Chernobyl nuclear accident is one of the most severe nuclear disasters in human history.