这句子少前又少后.真是郁闷啊
当你想到XX的时候,这（指代前面的XX）必然是个沉重的打击.
害我还去网上特意找了原文.
But we were recently informed by our surveyor that the whole roof will have to be replaced:【 which is of course a severe blow when you think】 it's only five years since we replaced the roof of the church itself.
就是：但是最近我们的考察员告发了一件事情——（教堂的）整个的屋顶都将不得不重新再换一次.（which就是指代前面的这句话看到了吗）当你想到我们换这个教堂的屋顶只有5年的时候,这无疑是个沉重的打击