Thanks to anyone who would help me fix this issue.
The Link is:
The above link is the category archive page.I want the sidebar same as NEWS&EVENTS page added to this page. I customized the twenty eleven theme. The plugin used for the news&events sidebar is WORDPRESS CATEGORY ARCHIVE.
You could see the single post has sidebar, the news&events has sidebar, only this page has no sidebar. I would this page have the same sidebar as the single post. I already added get_sidebar() to category.php, archive.php, single.php, page.php.
Thank you very much.