We are worried because we do not know how long they will stay or how we will take care of them.

VOA: standard.2009.10.27

" And-- "How long are you going to stay happy for?"

你们的快乐会持续多久“

哈佛公开课 - 幸福课课程节选

How long do you want to stay here?

要在这儿待多久？

How long实战 - SpeakingMax英语口语达人

Do you think that we have the stomach to stay there for as long as it takes to stablise the country, given how important it is We are going to stay there for as long as we do.

考虑到重要性,您认为我们能不能坚持到这个国家的稳定,我们会留在那里。

普林斯顿公开课 - 国际座谈会课程节选

How long will you stay here?

要在这儿待多久？

How long实战 - SpeakingMax英语口语达人