blue sky

基本解释

The white building was relieved against the blue sky.
这座白色建筑物在蓝天的衬托下显得十分突出。
There are different theories about why they call them Blue Sky Laws.
至于为什么把它叫做蓝天法,有很多不同的说法
Sometimes several clusters of white clouds drift across the blue sky.
蔚蓝色的天空中，时而飘过几朵白云。
《新英汉大辞典》

This was because all you could see was the very blue sky and the very hot sun.
I think it was because people were overselling investments and saying, there's no limit to this investment but the blue sky above.
我想这是因为,当时人们过度宣传投资产品,并宣称,投资收益无止境,如头顶的蓝天那么遥远
耶鲁公开课 - 金融市场课程节选
The problem with the Blue Sky Laws was that they were each state done separately and it was hard for states to manage what were, basically, national businesses.
蓝天法的问题在于,各州的法律都是分开制定的,由各州政府去处理,然而全国性的问题却无从解决
耶鲁公开课 - 金融市场课程节选

Mullins went on to release several LPs, including 1992's Better Days and 1994's Big Blue Sky.
NPR: From Station XPN: Shawn Mullins in Concert