Question

英语虚拟语气？

Thanks to their great efforts the old houses were saved,用虚拟语气如何改写

Answer 1

The old houses wouldn't have been saved if they had made no efforts.
与过去事实相反，从句用过去完成时，主句用would have done

Answer 2

Without their great efforts the old houses would not have been saved.没有他们的巨大努力，这些房子是不会得救的。
=But for their great efforts the hold houses would not have been saved.要不是因为他们的巨大努力，这些房子是不会得救的。