帮忙讲讲英语题 关于语法的 谢谢

why
adv.
为什么
They ask, 'Why did it happen? What should we do about it?'
大家问,'为什么会发生这样的事?我们该怎么办?
Why did you do it?
你为什么这样做？
Why don't we come more often?'
咱们干吗不经常不这里呢?'
I can't tell you why she is crying.
我不能告诉你她为什么哭。

W-did he go?
他为什么去?
W-did you write to him?
你为什么给他写信?
Do you know why he was late?
你知道他为什么迟到吗?
That's the reason why I wrote to him.
那就是我写信给他的原因。
That is (the reason) why he raised the question.
这就是他所以提出问题的原因。

why
conj. 连接词

为什么；…的理由
Do you know why he was late?
你知道他为什么迟到吗？
Geoffrey asked her why she was not amused.
杰弗里问她为什么不喜欢他的讲演。
That is why stone walls are used instead of fences around New England fields.
这就是为什么在新英格兰用石头墙而不用栅栏的原因。

个人意见：why是我们常说的wh-词的其中之一。他的用法基本上与what,where相同。但是它是对事情的原因提出问题。譬如：Why do you usually go to school on foot? 你可以回答：My home is near school so I do