tilt at windmills
作势挑战，故作姿态

讲解：

tilt at windmills的典故出自塞万提斯的《唐吉诃德》。书 中这位食古不化的骑士看到风车以为是火龙，挟着长矛就策 马而攻之。后来，tilt at windmills便引申为「向虚幻的敌人挑战、故作姿态」之意。

例句：

And [Congressman Jim] Cooper may be tilting at White House windmills largely to increase hisstature in anticipation of his campaign for the Senate next year，when a special election for Al Gore’s former seat is held-(出自：TIME, Dec. 13，1993，p. 39 )
众议员金古柏之所以要作势向白宫挑战，主要原因可能是想自抬 身价，来为明年补选高尔留下的参议院席位预做准备。