Great. On a windless day, if the engines are off the aircraft has neither airspeed nor groundspeed.

OK, now, let's place a conveyor belt under the aircraft's wheels, and bolt the plane to the ground by its nose, tail,and wingtips. Now, let's fire up the conveyor belt to 30mph.

It's still a windless day.
Answer these questions:
1) What's the aircraft airspeed?
2) What's the aircraft groundspeed?
3) What's the aircraft's wheelspeed on the conveyor?