洪灾

tè dà hóng zāi de kǎo yàn

特大洪灾的考验

the test of the severest floods

yìng duì wèi lái hóng zāi

应对未来洪灾

dealing with future floods

quán guó hóng zāi yù jǐng xì tǒng

全国洪灾预警系统

national flood warning system