The moon was full, the sky clear.

圆月碧空。

《牛津词典》

The sun was radiant in a clear blue sky.

湛蓝的天空阳光灿烂。

《牛津词典》

Blue sky, clear lakes, green grasslands and snowy mountains are all our treasures.

湛蓝的天空，清澈的湖水，碧绿的草原，雪山，都是我们的财富。

youdao

The next day the sky was blue and clear.

VOA: special.2009.02.28

The sky was just a little lighter blue than his suit, clear and even with only one cloud in it, a large, blinding white one with curls and a beard." Notice that image of the cloud, the blinding white cloud.

天空比他身上蓝色的西装颜色更亮，更清朗，甚至,空中只有一朵白云，是大而亮白的螺旋状和,胡须状，注意这多云的图像，一朵亮白的云。

耶鲁公开课 - 1945年后的美国小说课程节选

And one day, outof the blue clear sky, I got a letter from Jenny wondering if I couldcome down to Savannah and see her, and that'swhat I'm doing here.

VOA: standard.other

And all this interspersed by hours adrift on the river, planks and ropes gently creaking in the wind, the water dark and cool, the night sky clear above.

BBC: The perfect trip: Egypt

"The idea is that the same thing is true for colors, that there are certain kinds of colors that are characteristic of stuff that's good for us as a species -- clear sky, clear water -- and stuff that's bad for us, like rotting foods, biological waste products, " he said.

CNN: Is 'red' the same to all creatures?

The image transmission wasn't perfect and suffered defects because the Earth's atmosphere caused errors, even when the sky was clear, NASA said.

CNN: STORY HIGHLIGHTS