have your head in the clouds

to have ideas, plans, etc. that are not realistic
有不切實際的想法；離地

• The leader clearly had his head in the clouds to propose such a terrible plan. He should learn to be down-to-earth by listening to the voices of people.
  那個領䄂提出一個如此糟糕的計劃，真是很離地。他應聆聽民意，學習如何去貼地。