Indeed, what might Mercator have thought （由what引出主语从句）were （系词）it （表语）suggested （过去分词，做it的后置定语）to him that （由于suggest后面需要双宾语，这里的that引出直接宾语从句，前面的to him为介词短语）his scheme （从句中的主语）would one day be used to plot landscapes so far from terrestrial in aspect as （这里的so 应当同后面的as联系起来看，意思为“以致”）to reflect back确实,M可能会想到的是它暗示了他的这个预测计划会在将来被用...
