and what if someone is copying whatever u post not even changing a single word and giving the link of your site..... is there any way we can stop this?
Nope. If you publish it, it's fair game as long as people leave your resource box intact or give a link to the page where they got it from your site.
Source: Google Adsense Program Policies Send a DMCA notice to the site owner, if he/she doesn’t respond then send it to host and they will terminate their site’s hosting, you can also get them delisted from Google and Yahoo Index and get their adnsese account banned!
Duplicated content might not be against adsense rules, BUT: Sites made "just for adsense" are. You should add something more to your content sites.. add a forum, a poll, wiki, classifieds, a niche link directory. In other others: install a full-featured CMS to use that content (like drupal.org). It wil also help you market it, 'couse people like forums and classifies, and auction sites, it adds EVEN more value than unique content I BELIEVE personaly!