The fields covered with snow became a vast expanse of whiteness stretching to infinity.

田野被大雪覆盖，白茫茫的一眼望不到边。

《新英汉大辞典》

A vast expanse had melted away.

一大片冰川已经融化。

youdao

After the heavy snow, the fields were a vast expanse of whiteness.

下了一场大雪，田野上白茫茫一片。

youdao

You have this bureaucracy that's--it's not really a bureaucracy, but you've got these royal officials representing the royal will, but the actual impact in this vast expanse of the Russian empire isn't that great.

拥有庞大的官僚机构,并非是真正的官僚,但这些皇亲贵戚的确代表了王室的意愿,而实际上,它对幅员辽阔的俄国产生的影响绝非那般重大

耶鲁公开课 - 欧洲文明课程节选

The jihadists use the vast expanse of the Sahara to train recruits from across the region.

ECONOMIST: Al-Qaeda��s star is falling in Iraq but rising in the Maghreb

Their ages range from five to 14, and their accents range from all across China's vast expanse.

ECONOMIST: China��s schools for non-children

Unlike Antarctica, which has a treaty that prohibits territorial claims, there is no agreement for the vast expanse of the Arctic.

CNN: Countries in tug-of-war over Arctic resources