煞有其事

suǒ yǒu zhè xiē dìng yì suī rán tīng shàng qù shà yǒu qí shì dàn dōu jīng bu qǐ tuī qiāo

所有这些定义虽然听上去煞有其事，但都经不起推敲。

All these definitions, while sounding impressive, do not stand up under closescrutiny