zāi / biàn / shuō / rèn / wéi / dì / qiú / lì / shǐ / shàng / de / zhòng / dà / biàn / huà / shì / yóu / tū / rán / de / zāi / nàn / yǐn / qǐ / de

灾变说认为地球历史上的重大变化是由突然的灾难引起的。

Catastrophism holds that major changes in Earth's history were caused by sudden disasters.