You don't have to rate your story unless you are going to use sex scenes of any kind, or violence, then use 18+. [ NOTE: if you're under the age of 18, you can still read it, it's just to let you know what might be in the story so you know]
Swearings are actually fine to use in the story's. We just don't want you to swear at each other.
Questions are welcome =)