Pre-moderation of every post made to a community is not something we would recommend as a general rule or best-practise, however there may communities or scenarios where this would be needed.
Here are tools to help with pre-moderating your community:
Civil Tongue (Swear Word Filter)
Pre Moderated Category
Pre Moderating a Role
In addition to these specific plugins, you can also choose to moderate on a per-role basis by enabling the “Approval -> Require” permission. See main article on roles and permissions.
If you do not need to pre-approve every post before it appears on the forums, but would like to make sure all posts are verified by an Admin or Mod at some point, you may consider the Resolved plugin.