[pàn ruò tiān yuān]   

判    若    天    渊    高低差别就象天空和深渊那样悬殊。

判若天渊是词语，读作pàn ruò tiān yuān，形容两者相差极为悬殊。

It is as far apart as the sky and an abyss

判若两人    判然不同    判若水火    判若云泥    判若天渊