Training my human -- should I purrsist?

Dear George,
My name is Prudence, like you I am a black cat, and like you I am lively, highly intelligent and insatiably curious. Unfortunately my human Rose went off to university leaving me stuck at home with her rather dim mother, whom I have spent several years trying to train. I have managed to get her to understand a variety of very simple MEOWs: - Get Up its 5am! Open the door NOW! Any nice food in that bag? Catnip NOW! but we seem to be reaching her limit of understanding. 
Any ideas on how to extend her ability to learn would be most useful. I am getting bored of saying the same old meows every day. 
I do rather wish I could have gone to university too, perhaps to study human behaviour and cognition. Or mice.
Best wishes, Prudence

Dear Prudence, 
You have done well to train your older human so effectively. It will not be easy to improve her much more. Do you have the time and the patience to purrsist? You might try training her (if you have not already done so) to buy the right kind of cat food.
This requires self discipline, because it is done by refusing to eat inferior brands or, at least, pretending to eat with great reluctance, then covering the food as if it was something in the litter tray.  (Yes, you can of course eat this on the sly from the food recycling bin once she has thrown it out).  Loud purring when you get the right kind of food followed by a lot of rubbing against her will reward her. Most humans can learn which food to choose on the supermarket shelves.
I am sorry to hear about Rose. Humans that get obsessed with studying often suffer from stereotypic repetitive behaviour. Celia has been particularly trying lately, spending all her time on the computer and showing every sign of being stressed out. At her age she should know better and would do, if only she was a cat.
Many Oxford and Cambridge colleges have career opportunities as the college cat. Register with Felinked in. Purrsonally I wouldn't bother studying human behaviour at university - it is blinding obvious that the species is just thick.
Yours
George.
PS. More details of college cat life here.