i am using the TFS 2013 version and i want to deny the check ins without giving the work item ids. please suggest me how to make the work item type mandatory.
You should use check in policy to handle your scenario.
These check-in policies require the user to take actions when they conduct a check-in to source control, for example a user can be required to associate a work item with a changeset.
To create a check-in policy:
In the Check-in Policy list, select the policy type you want and then click OK.
In your case, just select Work Items, the policy is added to the list that a work item must be associated with the check in.
When you are satisfied with the settings for the check-in policies, click OK; the new check-in policy now displays with future check-ins. Others have to select related work item ID in pending changes page, otherwise he will not be able to check in code.
More details please take a look at this blog: Add Check-In Policies