It's called sleep away camp because they stay overnight (过夜) there.

这叫作睡眠营地，因为他们在这里过夜。

youdao

I suggest you stay overnight here for more examinations.

我建议你在这里过夜，做更多的检查。

youdao

The American contingent will stay overnight in London.

美国代表团将在伦敦留宿。

《柯林斯英汉双解大词典》

After an overnight stay in Mexico, President Obama departs for Trinidad and Tobago Friday to attend the Summit of the Americas.

VOA: standard.2009.04.17

Big campaign contributors were invited to stay overnight in the Lincoln bedroom at the White House?

参与的大手笔捐款人都被邀请,在白宫的林肯卧室留宿一晚？

耶鲁公开课 - 公正课程节选

If men stay overnight", they argued, "The costs to the college will increase."

她们反对道，留男士过夜会增加学校的开销“

耶鲁公开课 - 公正课程节选

But in truth, to experience Venice like a Venetian, all you need to do is to stay overnight.

BBC: Secret Venice

Stay overnight at a bed and breakfast for a taste of warm Scottish hospitality.

BBC: Exploring Scotland by road

Machu Picchu Sanctuary Lodge is the only hotel at the site if you want to stay overnight.

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