帮忙分析一个英语句子的句式结构This week work began on a project to re-establish agriculture should such a calamity occur书上给的翻译：本周,在假设灾难发生的情况下,致力于一项农业重建工程的做工开始启

Question

帮忙分析一个英语句子的句式结构
This week work began on a project to re-establish agriculture should such a calamity occur
书上给的翻译：本周,在假设灾难发生的情况下,致力于一项农业重建工程的做工开始启动
帮忙分析一下这个句子的句子成分,我弄不太顺
我弄不懂的地方就是【假设灾难发生】这个假设是从哪里译出来的?
这句话的主句是【This week should such a calamity occur】这个吗?

Answer 1

should引导的虚拟条件句放在句首要倒装=if such a calamity were to occur
should+动词原形)或“were to+动词原形”(表示与将来事实相反的假设)