休假归来后，她面临着一大堆文书工作。

She faced a ___mountain of paperwork after her holiday.

这家公司被堆积如山的债务所淹没。

The company is buried under a ___mountain of debt.

节庆活动结束后，志愿者们处理了堆积如山的垃圾。

After the festival, volunteers tackled a ___mountain of rubbish.