The sun was radiant in a clear blue sky.

湛蓝的天空阳光灿烂。

《牛津词典》

I let her play in the clear, blue sky.

我让她在清澈，蔚蓝的天空玩耍。

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In some of the pictures, the tops of the nearby Woolworth Building and other skyscrapers can just be seen above the enormous cloud of debris, gray against a clear blue sky.

在这些照惩中，这伍尔沃斯大楼的顶部和其它的摩天大楼仅仅看到巨大的瓦砾堆上的烟，灰色笼罩了明净的蓝天。

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" Jesse Nichols, a librarian on the Senate Finance Committee and the first black appointed to a clerical position in the Senate, recalled that "Senator Gore used to come in and out of the clear blue sky he would say, 'Jesse, bring me a Coca-Cola.

CNN: Excerpt: 'The Prince of Tennessee: The Rise of Al Gore'

But a clear, cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more easily than they do red light.

BBC: rainbow

Instead, again with data as crystal clear as an azure sky of deepest blue, the report identifies potential root causes in intellectual property, business practice and unforeseen technical challenges as playing a significant role, along with some areas where the FDA could help foster drug development.

FORBES: The Death Of The Blockbuster Drug: A Cheat Sheet