The program examined several bridge failures and other engineering disasters.这项计划检查了几处桥梁事故及其他工程上的重大灾祸。These policies could lead us to environmental catastrophe.这些政策会给我们的环境带来大灾祸。Erosion of the soil on the slopes is one of the great evils in this region.坡地土壤的冲蚀是本地区的大灾祸之一。