How can make Quote Box?

how can make Quote Box for comment?
example: Reply With Quote to sitepoin

<img src="http://sitepointstatic.com/forums/images/buttons/quote.gif" alt="Reply With Quote" border="0" title="Reply With Quote">

Look at what that image is linked to. Notice that it’s the URL of the reply page with the ID of the post you want to quote included. The reply page is using this ID from the URL to get the content of the post you’re quoting from the DB then putting it in the textarea.

Not Understand?

You need to pass the id of the thread/post/forum you’re replying to in the link, like so:-

<a href="reply.php?id=12345">Reply</a>