The researchers asked them if they napped and for how long.

研究人员询问他们是否午睡以及午睡多长时间。

youdao

For how long must I wait?

我要等多久？

youdao

The only question is for how long.

唯一的问题是，这能够持续多久。

youdao

As for how long the recession will last, Bryson predicts that the economy could turn positive by the end of the year.

VOA: standard.2009.03.18

How it ends up in the long run for the Dutch is that the Dutch cease to be a great power.

荷兰长远之后的下场,便是荷兰国力日衰,风光不再

耶鲁公开课 - 欧洲文明课程节选

I'm going to live here for, who knows how long. Quite a long time.

我打算定居在这儿，不知道多久。会是相当长一段时间。

追忆艾米 - SpeakingMax英语口语达人

We wanted to investigate to find out who knew what, when, and for how long.

CNN: IRS scandal needs more than a scapegoat

It was not clear when or for how long the Marshals Service lost track of them.

CNN: U.S. lost track of two with known or suspected terror ties

Peace has so far continued to reign in carrier land, but for how long?

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