A student driver.
If the vehicle is registered to you, then this is grand theft. Call the police and report it. If the vehicle is not owned by you, then it may be theirs and they have a perfect right to drive their own vehicle.
Someone who is slow at learning
No. * i say Depends on your policy. Call your insurance person.
a lunar rover
I guess an eager scholar?
A "Chauffeur"
A chauffeur
You would probably be insured for liability, but the car would not be insured for collision. However, to be sure, you should call your agent or read your policy.
Drive away quickly, pretending nothing happened.
"YOU" dont, the debtor does. call the lender.
helper
It depends, in some counties you can go straight to jail. In others they may simply give you a ticket for driving under suspension. They can also impound the vehicle or force you to call someone with a license to come get the vehicle.