多久

I don't know how long.

我不知道要多久

I don't know how long i'll be.

我不知道，这需要多久

I don't know how long it can also support ...

我不知道自己还可以支持多久。。。

This is a matter of how long?

这是多久的事情了？

I do not know how long, now this is my job.

我不知道能做多久，现在这是我的工作。

You don't know how long I've waited for you...

我不知道我等了你多久。。。

I don't know how long I can keep it up.

我不知道我能坚持多久。

You don't know how long I've waited for you.

你不知道我等了你多久了。

I don't know for how long.

我不知道还有多久。

How long have you been in China ?

你在中国多久了？

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐