A dark cloud loomed up over the horizon.

一片乌云突然出现在天际。

A solar phenomenon known as a sundog arcs over the tundra in Churchill, Manitoba, Canada.

/ 太阳的“假日”天文现半悬于加拿大Manitoba丘吉的天际。

The mountain was clearly defined against the eastern sky.

巅被东方的天际衬托得轮格外分明。

The mountain was silhouetted against the sky.

这座在天际映出黑色影。

Hills melt into the sky.

渐渐没入天际。