How on earth do you know about it

知道───know;到底───to the end

It is very useful for a person to know how to swim.───对一个人来说会游泳是很有用的.

I know you better than him.───我对你比对他更了解.

His secret died with him, and now we shall never know the truth.───他的秘密随他一起离去, 现在我们永远也不可能知道真相了.

Do you know the responsibilities of the government workers?───你知道政府工作人员的职责 吗 ?

Do you know how to manipulate a computer?───你知道如何使用计算机 吗 ?

All the actors know the play backward.───所有演员对剧本都熟知到可以倒背如流.

I'm curious to know what he said.───我很想知道他说了些什么.

The area can easily be worked out if you know the length and the breadth.───如果你知道长度与宽度,面积很容易计算出来.

I could not know that. I'm not telepathic.

'There's no one in.' 'How do you know?'

Would you know your daughter, see her in company.

When three know it, all know it.

To ask well is to know much.