air castle

美 [er ˈkæsl]英 [eə(r) ˈkɑːsl]

air castle

noun

absentminded dreaming while awake: Synonym: reverie revery daydream daydreaming oneirism castle in the air castle in Spain

数据来源：WordNet

1

Short of perfect Regional Innovation System , National Innovation System will be nothing else but air castle .

没有健全的区域创新体系，国家创新体系无异于空中楼阁。
2

Because of the disjoint of the theoretical and practical research of reading instruction , many theories can not be put into practice for proof-test finally . So the theory becomes an air castle without any practical applicable worth ;

关于阅读教学对话的理论研究与实践研究脱节，很多理论最终难以付诸实践和接受实践的检验，理论建构成为空中楼阁，缺乏实际应用价值；
3

Then Ibrahim looked once more in the surface of the diamond and saw a great web like that of a spider hanging in the air round the castle .

易卜拉欣又看了一次钻石面，这回看见一张蜘蛛网似的大网悬在空中，罩着城堡。