A person can be both student and expert (if he/she has the skills) and this, with the same unique email!

For example a student in Terminal S or Deug of Math may be able to do the duty of a student of 6th or 5th grade (and therefore in this role he/she is a "Prof"), leaving to him/her the duty to ensure the high quality of his/hel work to be well graded by students ... and in the same way be a student of a math teacher for his own curriculum.

Good Plan

Take advantage of the current period to sponsor students or experts' friends: this will bring you for each confirmed registration a free credit!