Currently NASA envisions a long stay for a crew at Mars, about 500 days.

美国宇航局现在设想让宇航员在火星上长期停留大约500天。

youdao

How long a stay did you have in mind?

你原打算待多长时间？

《牛津词典》

Take a deep breath and see how long you can stay underwater.

深吸一口气，看你能在水里待多久。

《牛津词典》

And are any dorms open all year so international students can have a place to stay during long vacations?

VOA: special.2009.03.26

He done gone off with a woman and made me come but she ain't going to stay for long."

他和一个女人跑了,不过那个女人也不会跟他待多久的“

耶鲁公开课 - 1945年后的美国小说课程节选

So I'd be forced to stay a long time and not enjoy myself.

我就不得不被迫留下来，却玩得不尽兴。

I'm going实战 - SpeakingMax英语口语达人

They seem prepared for a long stay, setting up a makeshift hospital and erecting tents.

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That idea also applies to international level, where hotel costs can add up over a long stay.

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Butterflies and virtually fragrant flowers, often indistinguishable from each other, evoke an Eden-like harmony and invite a long stay.

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