How do you know what to buy, though?

但是，你怎么知道该买哪份报纸呢？

youdao

How do you know what the problem is?

那么怎样才能知道问题出在那里呢？

youdao

So, how do you know what to ask and when?

所以，你怎么知道何时该如何向面试官提问呢？

youdao

what Matt would have done?" "How do you know "Now you're setting up a date with a vampire! What do you have, a death wish?"

VOA: special.2010.01.20

Depending on what kind of chemistry you go in to, you might accidentally memorize parts of the table, which is fine, but what you really want to know how to do is know how to use the periodic table.

取决于你今后从事哪个方向的化学研究，你可能会不经意地记住周期表的某一部分，这就够了，但是要注意,你真正需要知道的是如何使用元素周期表。

麻省理工公开课 - 化学原理课程节选

And yeah, I know you know how to do it, but let's think about what might happen if I wanted to do that.

对，我知道你们知道该怎么做，那么让我们看看如果我,想要完成的话会发生什么。

麻省理工公开课 - 计算机科学及编程导论课程节选

So how do you know what people around you know?

FORBES: Magazine Article

How do you know what someone expects of you?

FORBES: Retailers: Who Do You Trust?

How do you know what you will inherit?

BBC: Miliband defends backing public sector pay freeze