"真的吗？我还能活多久？"男孩又问他妈妈。

"Really? <em>How</em> <em>long</em> can I live?" The boy asked his mother again.

“你要呆多久?““我无所谓。

<em>How</em> <em>long</em> are you staying?' 'I'm not fussy.

他估计自己当经理还有多久?

<em>How</em> <em>long</em> does he reckon he'll last as manager?

你工作多久了?

<em>How</em> <em>long</em> have you been working?

我必须在这里待多久才能等到答复？

<em>How</em> <em>long</em> must I bide here to wait for the answer?

你认识你未婚妻（或未婚夫）多久了？

[as noun betrothed]<em>how</em> <em>long</em> have you known your betrothed?

你知道那些耍笔杆的家伙要多久才能给我们许可吗?

Do you know <em>how</em> <em>long</em> it takes for those pen-pushers to give us the OK?

塔比瑟不知道那个女人已经靠这条水道坚持生活多久了。

Tabitha wondered <em>how</em> <em>long</em> the woman had been scratching a living on the waterways.

我们到底要等多久，你向大家交个底吧。

<em>How</em> <em>long</em> do we have to wait? You’d better put everybody in the picture.

如果没有外界的帮助，我真不知道他们还能撑持多久。

I wonder <em>how</em> <em>long</em> they can hold/carry on without outside assistance.