Castles in Spain

• Don’t build castles in Spain all day long. (別整天做白日夢) (正)
• Don’t build castles in Portugal all day long. (誤)

解說：(to build) castles in Spain 為固定用語，意為「(做) 白日夢；(築) 空中樓閣」，與 castles in the air 同義。