Post a comment against a url

If you add a facebook plugin in your site and comment on it, that comments are stored against a url(i.e. you开发者_开发知识库r site url) and you can retrieve all those comments by using graph api like below : https://graph.facebook.com/comments/?ids=< URL >.

Here is my question : how to post a comment using graph api for the same url ?

Thanks,Ranjith