The sky was clear and studded with stars.

天空晴朗，繁星点点。

《牛津词典》

The sky was clear; the streets, blissfully still.

天空清澈；街道安详寂静。

youdao

But it was a beautiful August day; the sky was clear, his spirits high.

但是美丽的八月和清澈的天空让他精神振作了起来。

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

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

The sky was clear and the sun shone brightly on a heavy snow pack, but it was cold and the wind was blowing.

WSJ: Escape From a North Korean Prison

Our only feedback for ASUS here is that the locations of some of the photos were a bit off (for instance, this author was never on the north bank in the above map), which is weird considering the sky was clear at the time, plus there weren't many tall buildings.

ENGADGET: ASUS PadFone 2 review: two times is a charm for this phone-in-tablet combo