Use Case Review 2

Review 2 by Egemen

1. In Rate Each Other use case, it may be better to just say Rate or Give Rating.
2. I am still unsure about the info we require at the registering process. Also, Google or Facebook sign-ins should be considered.
3. Get Feedback From An Expert On The Language use case should be renamed to Get Grading From Another User. Where does getting feedback use case fit in, I do not know. Let's not use 'expert' word, and split feedback into grading and feedback. Rate The Reviewer and Comment On The Reviewer
4. Is Take Exercises About The Notes use case necessary, I do not know. If it is not necessary, let us remove it.
5. Maybe Select A New Language is more appropriate here. But then, users can only take proficiency at the selection, which is not correct behavior. I am unsure.
6. Can admins learn a language? Can they do or grade assignments? If yes, then diagram must be modified.