A dark cloud loomed up over the horizon.

一片乌云突在天际。

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

/ 太阳的“假日”天文象半悬于加拿大Manitoba丘吉尔苔原的天际。

The mountain was clearly defined against the eastern sky.

山巅被东方的天际衬托得轮格外分明。

The mountain was silhouetted against the sky.

这座山在天际映黑色影象。

Hills melt into the sky.

群山渐渐没入天际。